Creatine on the Certainty Pyramid - Requirements, Risks and Myths Rebuilt from Primary Literature (2015\u20132026)<\/title>\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n<link href=\"https:\/\/fonts.googleapis.com\/css2?family=Archivo:wght@500;600;700;800&family=Source+Serif+4:ital,opsz,wght@0,8..60,400;0,8..60,600;1,8..60,400&family=IBM+Plex+Mono:wght@400;500;600&display=swap\" rel=\"stylesheet\">\n<style>\n:root{\n --paper:#E9EDEF;\n --paper-deep:#DBE1E5;\n --paper-lift:#F2F5F6;\n --ink:#16232B;\n --ink-soft:#4A5B66;\n --ink-faint:#7E8D96;\n --signal:#14556E;\n --signal-deep:#0C3A4D;\n --contest:#A96F21;\n --flag:#95291F;\n --rule:#BCC7CD;\n\n \/* five-step certainty ramp \u2014 solid fills only, no hatching *\/\n --t1:#093644; \/* highest certainty *\/\n --t2:#14556E;\n --t3:#3F6B7E;\n --t4:#96600B; \/* emerging \/ individual *\/\n --t5:#A63525; \/* contested or debunked apex *\/\n\n 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3.4rem;font-family:var(--mono);font-size:0.78rem;color:var(--ink-soft)}\nfooter p{max-width:90ch}\n\n@media (max-width:640px){\n table{display:block;overflow-x:auto;white-space:nowrap}\n table.wrapok{white-space:normal}\n}\n@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}\n<\/style>\n<\/head>\n<body>\n<div class=\"shell\">\n\n<header class=\"hero\">\n <div class=\"kicker\">EVIDENCE REVIEW \u00b7 SUPPLEMENT DOSSIER N\u00ba 2 \u00b7 COMPANION TO \u201cHUMAN NUTRIENT REQUIREMENTS\u201d<\/div>\n <h1>Facts About Creatine<\/h1>\n Requirements, kidneys (including the full long-term record), water, liver, skin, muscle, brain, women\u2019s health (bone, mood, pregnancy, menopause \u2014 trial by trial), men\u2019s health, co-ingestion with other nutrients and supplements, and overdose \u2014 rebuilt from primary literature, 2015\u20132026, with independent studies weighted above commercial ones and the popular beliefs put on trial.<\/p>\n <div class=\"hero-meta\">\n METHOD primary papers & meta-analyses, live-searched<\/b><\/span>\n WINDOW 2015\u20132026 (anchors to 2009 where provenance demands)<\/b><\/span>\n GRADING five-tier certainty ramp, solid fills<\/b><\/span>\n FUNDING independence flagged per source<\/b><\/span>\n <\/div>\n<\/header>\n\n<section id=\"caveat\">\n <div class=\"callout\">\n Standing verification caveat \u2014 preserved from the parent project<\/span>\n Every effect estimate, confidence interval, sample size and trial figure in this document was drawn from live literature search of the sources listed in the references, but must be independently verified against the primary PDFs<\/strong> before publication, clinical use, or citation in derivative work. Several 2025\u20132026 papers are recent enough that corrections may follow. This is a scientific literature review, not individualised medical advice: anyone pregnant, with kidney or liver disease, under 18, or on medication should involve a physician or registered dietitian before supplementing.<\/p>\n <\/div>\n <div class=\"callout amber\">\n Funding-independence note \u2014 read before the findings<\/span>\n Creatine research has an unusual structure: the most-cited review authors (the ISSN cluster \u2014 Kreider, Antonio, Candow, Forbes, Smith-Ryan, Ostojic and colleagues) are rigorous and prolific, but many disclose funding or advisory ties to creatine manufacturers, and several defining \u201cmisconceptions\u201d reviews appear in the ISSN\u2019s own journal. That does not make them wrong \u2014 most of their claims are independently replicated \u2014 but throughout this document each major conclusion is anchored, wherever possible, on groups outside<\/em> that cluster: nephrology teams in Iran and Brazil, the UNSW exercise-science group in Australia, and the Forschungszentrum J\u00fclich neuroscience institute in Germany. Every reference carries a tag: INDEPENDENT<\/span> ISSN-CLUSTER<\/span> COMMERCIAL<\/span>. Where only industry-adjacent evidence exists \u2014 the skin section is the clearest case \u2014 the text says so plainly.<\/p>\n <\/div>\n<\/section>\n<section id=\"pyramid\">\n The organising figure<\/span>\n <h2>Where creatine\u2019s claims sit on the certainty ladder<\/h2>\n The tier ladder keeps the parent project\u2019s grammar in a more legible form: bar length encodes evidentiary weight, colour depth encodes certainty<\/strong>, and the bottom rung is deliberately short because it is where arguments live, not where effects are. What is unusual about creatine is that a fifth stratum is needed below the usual contested tier \u2014 a debunked shelf, because several of the most widely believed claims about creatine (kidney destruction, dehydration, hair loss, steroid equivalence) have been tested and have failed.<\/p>\n\n <figure aria-label=\"Five-tier certainty ladder for creatine claims\">\n <svg viewBox=\"0 0 940 640\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Certainty ladder for creatine, five tiers, bar length encodes evidentiary weight<\/title>\n\n \n <line x1=\"210\" y1=\"46\" x2=\"900\" y2=\"46\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <polygon points=\"900,46 886,39 886,53\" fill=\"#16232B\"\/>\n <text x=\"210\" y=\"34\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">BAR LENGTH = EVIDENTIARY WEIGHT (participants \u00d7 replications)<\/text>\n\n \n <line x1=\"40\" y1=\"70\" x2=\"40\" y2=\"600\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <polygon points=\"40,600 33,586 47,586\" fill=\"#16232B\"\/>\n <text x=\"30\" y=\"335\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\" transform=\"rotate(-90 30 335)\" text-anchor=\"middle\">CERTAINTY DECREASES \u2193 \u00b7 colour ramp #093644 \u2192 #A63525<\/text>\n\n \n <rect x=\"70\" y=\"70\" width=\"130\" height=\"92\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"135\" y=\"106\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 1<\/text>\n <text x=\"135\" y=\"128\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">HIGH<\/text>\n <rect x=\"210\" y=\"70\" width=\"690\" height=\"26\" fill=\"#093644\"\/>\n <text x=\"210\" y=\"118\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Replicated RCTs & tracer-method meta-analyses<\/text>\n <text x=\"210\" y=\"138\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">creatinine-rise-without-injury artifact \u00b7 safety 3\u20135 g\/d in healthy adults \u00b7<\/text>\n <text x=\"210\" y=\"156\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">repeated-sprint strength \u00b7 no dehydration\/cramping causation<\/text>\n\n \n <rect x=\"70\" y=\"180\" width=\"130\" height=\"92\" fill=\"#14556E\" rx=\"3\"\/>\n <text x=\"135\" y=\"216\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 2<\/text>\n <text x=\"135\" y=\"238\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">MODERATE<\/text>\n <rect x=\"210\" y=\"180\" width=\"545\" height=\"26\" fill=\"#14556E\"\/>\n <text x=\"210\" y=\"228\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Consistent meta-analytic signal, confounds known<\/text>\n <text x=\"210\" y=\"248\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">lean mass +1.0\u20131.4 kg pooled (water-confounded; UNSW dissent) \u00b7 cognition<\/text>\n <text x=\"210\" y=\"266\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">under metabolic stress \u00b7 women\u2019s strength with training<\/text>\n\n \n <rect x=\"70\" y=\"290\" width=\"130\" height=\"92\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"135\" y=\"326\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 3<\/text>\n <text x=\"135\" y=\"348\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">EMERGING<\/text>\n <rect x=\"210\" y=\"290\" width=\"400\" height=\"26\" fill=\"#3F6B7E\"\/>\n <text x=\"210\" y=\"338\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Small trials, plausible mechanism<\/text>\n <text x=\"210\" y=\"358\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">menopause muscle\/bone \u00b7 depression augmentation \u00b7 single-dose brain rescue \u00b7<\/text>\n <text x=\"210\" y=\"376\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">dietary-insufficiency epidemiology<\/text>\n\n \n <rect x=\"70\" y=\"400\" width=\"130\" height=\"92\" fill=\"#96600B\" rx=\"3\"\/>\n <text x=\"135\" y=\"436\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 4<\/text>\n <text x=\"135\" y=\"458\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">CONTESTED<\/text>\n <rect x=\"210\" y=\"400\" width=\"260\" height=\"26\" fill=\"#96600B\"\/>\n <text x=\"210\" y=\"448\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Contested or insufficient evidence<\/text>\n <text x=\"210\" y=\"468\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">proposed DRIs \u00b7 hypertrophy at 5 g\/d \u00b7 pregnancy use \u00b7 pre-existing CKD \u00b7<\/text>\n <text x=\"210\" y=\"486\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">topical skin claims (commercial)<\/text>\n\n \n <rect x=\"70\" y=\"510\" width=\"130\" height=\"92\" fill=\"#A63525\" rx=\"3\"\/>\n <text x=\"135\" y=\"546\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 5<\/text>\n <text x=\"135\" y=\"568\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">DEBUNKED<\/text>\n <rect x=\"210\" y=\"510\" width=\"130\" height=\"26\" fill=\"#A63525\"\/>\n <text x=\"210\" y=\"558\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#95291F\">Tested and failed<\/text>\n <text x=\"210\" y=\"578\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#95291F\">kidney destruction \u00b7 hair loss \u00b7 dehydration \u00b7 steroid claims \u00b7<\/text>\n <text x=\"210\" y=\"596\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#95291F\">mandatory loading \u00b7 \u201cwomen get bulky\u201d<\/text>\n <\/svg>\n <figcaption>Fig. 1 \u2014 The creatine certainty ladder.<\/b> Bar length encodes evidentiary weight; colour depth encodes certainty, descending from replicated-RCT territory to the debunked shelf. Tier assignments are argued claim-by-claim in the sections below, each with effect sizes, sample sizes and funding tags. Note the inversion versus folklore: the claims the public fears most (kidneys, hair, dehydration) sit at the debunked end; the claim the industry sells hardest (extra muscle at 5 g\/day) sits one tier lower than commonly assumed.<\/figcaption>\n <\/figure>\n<\/section>\n\n<section id=\"requirement\">\n Physiology first<\/span>\n <h2>How much does a body actually need?<\/h2>\n The gym-culture \u201crequirement\u201d of 5 g\/day is a supplementation dose, not a biological need<\/strong> \u2014 the first popular belief to challenge. Physiologically, total daily turnover is about 2 g\/day<\/span> in a typical adult, met roughly half-and-half by endogenous synthesis and diet (Brosnan & Brosnan 2016; Brosnan 2011). Creatine is a non-proteinogenic amino-acid derivative built from three amino acids: arginine + glycine<\/strong> (via AGAT in kidney, pancreas and liver, forming guanidinoacetate) then methylated by methionine<\/strong> as S-adenosylmethionine (via GAMT, mainly hepatic). That last step is expensive \u2014 creatine synthesis consumes on the order of ~40%<\/span> of the body\u2019s SAMe methylation budget, which is why the precursor amino acids matter as much as creatine itself, and why low-protein diets quietly strain the system.<\/p>\n\n <figure aria-label=\"Daily creatine budget diagram\">\n <svg viewBox=\"0 0 940 400\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Daily creatine budget: losses, synthesis and dietary supply<\/title>\n \n <text x=\"30\" y=\"34\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"16\" fill=\"#16232B\">DAILY CREATINE BUDGET (reference 75 kg man \/ 60 kg woman)<\/text>\n\n \n <rect x=\"30\" y=\"70\" width=\"300\" height=\"112\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"46\" y=\"98\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">ENDOGENOUS SYNTHESIS \u2248 73%<\/text>\n <text x=\"46\" y=\"122\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">arginine + glycine \u2014AGAT\u2192 GAA<\/text>\n <text x=\"46\" y=\"140\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">GAA + methionine\/SAMe \u2014GAMT\u2192 creatine<\/text>\n <text x=\"46\" y=\"164\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#B9CDD6\">consumes ~40% of SAMe methylation budget<\/text>\n\n \n <rect x=\"30\" y=\"196\" width=\"300\" height=\"96\" fill=\"#14556E\" rx=\"3\"\/>\n <text x=\"46\" y=\"224\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">DIET \u2248 27% \u00b7 a \u201ccarninutrient\u201d<\/text>\n <text x=\"46\" y=\"248\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">meat, fish, dairy only \u00b7 plants: 0 g<\/text>\n <text x=\"46\" y=\"266\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">US adult mean intake 1.38 g\/d; 42.8% <1 g\/d<\/text>\n\n \n <line x1=\"330\" y1=\"126\" x2=\"430\" y2=\"180\" stroke=\"#093644\" stroke-width=\"3\"\/>\n <line x1=\"330\" y1=\"244\" x2=\"430\" y2=\"200\" stroke=\"#14556E\" stroke-width=\"3\"\/>\n <polygon points=\"430,180 418,170 420,186\" fill=\"#093644\"\/>\n <polygon points=\"430,200 418,196 421,210\" fill=\"#14556E\"\/>\n\n \n <rect x=\"436\" y=\"112\" width=\"230\" height=\"150\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"551\" y=\"146\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">TOTAL BODY POOL<\/text>\n <text x=\"551\" y=\"170\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">~120\u2013130 mmol\/kg dry muscle<\/text>\n <text x=\"551\" y=\"190\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">~95% in skeletal muscle<\/text>\n <text x=\"551\" y=\"210\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">rest: brain, heart, retina,<\/text>\n <text x=\"551\" y=\"228\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">testes, blood<\/text>\n\n \n <line x1=\"666\" y1=\"187\" x2=\"760\" y2=\"187\" stroke=\"#95291F\" stroke-width=\"3\"\/>\n <polygon points=\"760,187 748,180 748,194\" fill=\"#95291F\"\/>\n\n \n <rect x=\"764\" y=\"120\" width=\"150\" height=\"134\" fill=\"#95291F\" rx=\"3\"\/>\n <text x=\"839\" y=\"150\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13.5\" fill=\"#FFFFFF\">IRREVERSIBLE LOSS<\/text>\n <text x=\"839\" y=\"174\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#F4DEDA\">\u2192 creatinine \u2192 urine<\/text>\n <text x=\"839\" y=\"200\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#F4DEDA\">men 20 mg\/kg\/d<\/text>\n <text x=\"839\" y=\"218\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#F4DEDA\">women 15 mg\/kg\/d<\/text>\n\n \n <rect x=\"30\" y=\"316\" width=\"884\" height=\"1.5\" fill=\"#BCC7CD\"\/>\n <text x=\"30\" y=\"348\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#4A5B66\">TURNOVER \u2248 2 g\/d \u00b7 proposed Adequate Intake (Ostojic 2026, unratified): men 5.4 mg\/kg\/d \u2248 400 mg \u00b7 women 4.1 mg\/kg\/d \u2248 240 mg<\/text>\n <text x=\"30\" y=\"372\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#95291F\">SUPPLEMENT DOSES sit 8\u201350\u00d7 above the proposed dietary AI: maintenance 3\u20135 g\/d \u00b7 loading 20 g\/d (optional, never mandatory)<\/text>\n <\/svg>\n <figcaption>Fig. 2 \u2014 The daily creatine budget.<\/b> Loss estimates and the 73\/27 synthesis-to-diet split are from the 2026 DRI proposal (Ostojic, Nutrition Reviews<\/i>); pool size and distribution from Candow et al. 2025; intake distributions from NHANES analyses. The DRI values are a serious proposal from a single researcher, not a ratified reference \u2014 placed at Tier 4 accordingly.<\/figcaption>\n <\/figure>\n\n <div class=\"stat-row\">\n <div class=\"stat\">\u2248 2 g\/d<\/span>total physiological turnover, adult omnivore (Brosnan 2016)<\/span><\/div>\n <div class=\"stat\">2.7\u00d7<\/span>precursor-derived synthesis capacity vs dietary creatine intake, NHANES III, n = 29,945 (Nedeljkovic & Ostojic 2025)<\/span><\/div>\n <div class=\"stat contest\">42.8%<\/span>of US adults below 1 g\/d dietary creatine; ~60% of 4,291 children, 17% consuming zero (Ostojic 2021)<\/span><\/div>\n <div class=\"stat flag\">0 g<\/span>dietary creatine on vegan diets \u2014 a carninutrient absent from all plant foods; vegetarians show measurably lower muscle stores<\/span><\/div>\n <\/div>\n\n Challenge to the popular belief:<\/strong> \u201ceveryone needs to supplement\u201d and \u201cnobody needs to supplement\u201d are both wrong. A healthy omnivore synthesises and eats enough to hold the pool. The genuinely exposed groups are vegans\/vegetarians (zero dietary supply), older adults with low meat intake, and possibly people on chronic low-protein diets \u2014 for whom the precursor amino acids (glycine, arginine, methionine) are also the constraint. NHANES associations linking <1 g\/day intake to higher all-cause mortality (HR 0.85 for \u22651 g\/d, 95% CI 0.72\u20131.00, 19.8-yr follow-up) are observational Tier-3 evidence at best: recall-based intake, single 24-h snapshots, and meat intake as an obvious confounder.<\/p>\n<\/section>\n\n<section id=\"muscle\">\n Muscles & strength<\/span>\n <h2>The biggest pro-creatine belief, put on trial<\/h2>\n Here the strongest independent<\/em> evidence pushes against the marketing, not for it. The 2025 UNSW randomized trial (Desai, Pandit \u2026 Hagstrom, Nutrients<\/i>) did what almost no prior trial had done: it inserted a 7-day non-exercise wash-in<\/strong> before training began, so the fluid effect of creatine could be separated from actual tissue growth. Sixty-three adults (34 women, 29 men, 31 \u00b1 8 y) took 5 g\/day or served as controls, then both groups trained identically for 12 weeks.<\/p>\n\n <figure aria-label=\"UNSW trial lean body mass timeline\">\n <svg viewBox=\"0 0 940 420\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>UNSW 2025 trial: lean body mass change over wash-in and training phases<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">LEAN BODY MASS CHANGE (kg, DXA) \u2014 UNSW RCT, n=63, 5 g\/day vs control<\/text>\n\n \n <line x1=\"90\" y1=\"330\" x2=\"880\" y2=\"330\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <line x1=\"90\" y1=\"70\" x2=\"90\" y2=\"330\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n \n <text x=\"78\" y=\"334\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">0<\/text>\n <line x1=\"86\" y1=\"245\" x2=\"880\" y2=\"245\" stroke=\"#BCC7CD\" stroke-width=\"1\"\/>\n <text x=\"78\" y=\"249\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">+1<\/text>\n <line x1=\"86\" y1=\"160\" x2=\"880\" y2=\"160\" stroke=\"#BCC7CD\" stroke-width=\"1\"\/>\n <text x=\"78\" y=\"164\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">+2<\/text>\n <line x1=\"86\" y1=\"75\" x2=\"880\" y2=\"75\" stroke=\"#BCC7CD\" stroke-width=\"1\"\/>\n <text x=\"78\" y=\"79\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">+3<\/text>\n\n \n <line x1=\"300\" y1=\"70\" x2=\"300\" y2=\"330\" stroke=\"#7E8D96\" stroke-width=\"1\" stroke-dasharray=\"5 5\"\/>\n <text x=\"195\" y=\"356\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">WASH-IN \u00b7 7 d \u00b7 no exercise<\/text>\n <text x=\"590\" y=\"356\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">RESISTANCE TRAINING \u00b7 12 wk \u00b7 3 sessions\/wk<\/text>\n\n \n <polyline points=\"90,330 300,287 860,117\" fill=\"none\" stroke=\"#093644\" stroke-width=\"4\"\/>\n <circle cx=\"300\" cy=\"287\" r=\"6\" fill=\"#093644\"\/>\n <circle cx=\"860\" cy=\"117\" r=\"6\" fill=\"#093644\"\/>\n \n <polyline points=\"90,330 300,330 860,160\" fill=\"none\" stroke=\"#96600B\" stroke-width=\"4\"\/>\n <circle cx=\"300\" cy=\"330\" r=\"6\" fill=\"#96600B\"\/>\n <circle cx=\"860\" cy=\"160\" r=\"6\" fill=\"#96600B\"\/>\n\n \n <text x=\"312\" y=\"278\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#093644\">+0.51 \u00b1 1.79 kg before any training (p=0.03)<\/text>\n <text x=\"312\" y=\"296\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#95291F\">\u2014 interpreted as fluid, not muscle<\/text>\n <text x=\"640\" y=\"100\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#093644\">creatine 5 g\/d<\/text>\n <text x=\"640\" y=\"196\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#96600B\">control<\/text>\n <text x=\"520\" y=\"240\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13.5\" fill=\"#16232B\">training gain \u2248 2 kg in BOTH groups<\/text>\n <text x=\"520\" y=\"258\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">between-group difference p = 0.71 (null)<\/text>\n <\/svg>\n <figcaption>Fig. 3 \u2014 The wash-in that changed the question.<\/b> Values from Desai et al. 2025 (10.3390\/nu17061081), independent of supplement funding at design level. The early gain \u2014 larger in women (+0.59 \u00b1 1.61 kg, p=0.04) \u2014 appeared before a single training session<\/b>, which is why the authors read it as fluid. Senior author Hagstrom: the benefits of creatine \u201cmay have been overestimated in the past, due to methodological problems with previous studies,\u201d and 5 g\/day \u201cis not enough if you\u2019re taking it for the purposes of building muscle.\u201d Prior no-wash-in trials credited creatine with ~1 kg extra muscle over 4\u201312 weeks.<\/figcaption>\n <\/figure>\n\n Against the UNSW null stands the pooled literature: a 2025 dose\u2013response meta-analysis of 61 trials<\/span> found creatine increased fat-free mass by +1.39 kg (95% CI 1.07\u20131.70)<\/span> and body mass by +0.89 kg<\/span>, with no effect on fat mass META<\/span>. But nearly all constituent trials used DXA or similar methods that cannot distinguish intracellular water from contractile tissue<\/strong> \u2014 exactly the confound UNSW isolated. At the elite end, an independent Spanish RCT in 23 professional U23 cyclists found 20 g\/day for 6 days produced no consistent benefit<\/strong> on recovery, body composition or performance RCT<\/span>. And in frail older adults, two pooled trials (n=106, ~6 g\/day, 14\u201316 weeks of training) showed training worked but creatine added nothing.<\/p>\n\n <div class=\"callout blue\">\n Honest synthesis \u2014 Tier 1 vs Tier 2 split<\/span>\n Tier 1 (keep):<\/strong> creatine reliably raises muscle phosphocreatine and improves repeated short high-intensity efforts \u2014 strength and power capacity across hundreds of trials since the 1990s. Tier 2 (demote):<\/strong> the lean-mass<\/em> benefit at 3\u20135 g\/day is smaller than folklore claims and partly a water artifact; the UNSW authors suggest ~10 g\/day may be the hypertrophy-relevant dose, but that has not yet been tested in a dedicated RCT. The popular belief \u201ccreatine builds muscle by itself\u201d fails; \u201ccreatine lets you train harder, and training builds muscle\u201d survives.<\/p>\n <\/div>\n<\/section>\n<section id=\"kidney\">\n The kidney question<\/span>\n <h2>Kidneys: the myth runs both ways \u2014 and both extremes fail<\/h2>\n Gym forums say creatine destroys kidneys; supplement marketing says it is \u201cproven completely safe.\u201d The 2025\u20132026 nephrology literature \u2014 largely from groups with no supplement-industry ties<\/strong> \u2014 supports neither extreme. The mechanistic core is an artifact: supplemental creatine degrades non-enzymatically to creatinine, the very molecule used to estimate kidney function<\/strong>. Serum creatinine rises, creatinine-based eGFR falls, and no injury has occurred.<\/p>\n\n <figure aria-label=\"Creatinine artifact chart\">\n <svg viewBox=\"0 0 940 430\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Kidney outcomes under creatine: creatinine-based estimates versus tracer-measured GFR<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">SAME KIDNEYS, TWO MEASUREMENTS \u2014 meta-analysis of 26 RCTs, n=1,036 (Int Urol Nephrol 2026)<\/text>\n\n \n <line x1=\"470\" y1=\"70\" x2=\"470\" y2=\"340\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <text x=\"470\" y=\"360\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">0 = no change vs placebo<\/text>\n\n \n <text x=\"60\" y=\"112\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Serum creatinine<\/text>\n <rect x=\"470\" y=\"92\" width=\"150\" height=\"34\" fill=\"#A63525\"\/>\n <text x=\"632\" y=\"115\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#95291F\">+0.14 mg\/dL (95% CI 0.05\u20130.22) \u2014 RISES<\/text>\n\n \n <text x=\"60\" y=\"154\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">eGFR \u2014 creatinine-based estimate<\/text>\n <rect x=\"290\" y=\"162\" width=\"180\" height=\"34\" fill=\"#A63525\"\/>\n <text x=\"60\" y=\"204\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#95291F\">\u221210.75 mL\/min \u2014 \u201cFALLS\u201d (artifact of the molecule being measured)<\/text>\n\n \n <text x=\"60\" y=\"252\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">GFR \u2014 Cr-EDTA tracer (true measurement)<\/text>\n <rect x=\"470\" y=\"232\" width=\"66\" height=\"34\" fill=\"#093644\"\/>\n <text x=\"548\" y=\"255\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#0C3A4D\">+5.89 mL\/min (95% CI \u22120.30 to 12.08, p=0.06) \u2014 NO DECLINE<\/text>\n\n \n <text x=\"60\" y=\"294\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Serum urea \u00b7 albuminuria \u00b7 proteinuria \u00b7 urinary creatinine<\/text>\n <rect x=\"462\" y=\"302\" width=\"16\" height=\"34\" fill=\"#3F6B7E\"\/>\n <text x=\"490\" y=\"325\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#3F6B7E\">no significant differences \u2014 injury markers silent<\/text>\n\n <text x=\"30\" y=\"394\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">Concordant independent meta-analyses: BMC Nephrology 2025 (21 studies; creatinine MD +0.07, GFR n.s.) \u00b7<\/text>\n <text x=\"30\" y=\"412\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#4A5B66\">J Renal Nutrition 2019 (Brazil; \u201cdoes not induce renal damage\u201d) \u00b7 J Renal Nutrition 2026 (Tsiaras; creatinine +0.13 mg\/dL, 19 RCTs)<\/text>\n <\/svg>\n <figcaption>Fig. 4 \u2014 The creatinine artifact, quantified.<\/b> When kidney function is measured with a tracer that does not depend on creatinine (Cr-EDTA), the \u201cdecline\u201d vanishes. The 2026 meta-analysis authors: findings \u201clikely reflect altered creatinine metabolism rather than kidney injury.\u201d All four meta-analyses are from nephrology\/renal-nutrition groups independent of the ISSN cluster.<\/figcaption>\n <\/figure>\n\n What survives scrutiny on the cautious side:<\/strong> nobody has run long RCTs in people with pre-existing chronic kidney disease \u2014 trials in type 2 diabetics, peripheral artery disease and hemodialysis patients show no injury signal, but they are short and small. Rare case reports (including one acute tubular necrosis) exist but are confounded and number in single digits against tens of thousands of trial participants. The one real-world harm<\/em> is diagnostic: an artifactually raised creatinine can trigger misdiagnosis, unnecessary work-ups, or wrongly adjusted drug doses. Anyone supplementing should tell their physician; confirmation should use cystatin C or measured GFR, not creatinine-based eGFR.<\/strong><\/p>\n\n <h3>The long-term record, trial by trial \u2014 does chronic intake damage the kidney?<\/h3>\n To answer the long-term question directly, here is every substantive long-duration human dataset located in this research pass, with method quality noted. The pattern is consistent: no study using an injury-capable method has detected kidney damage in people with healthy kidneys<\/strong>, across exposures from 12 weeks to 5 years and doses to ~10 g\/day \u2014 while the honest gaps (pre-existing CKD, decades-long unsupervised use) remain unfilled.<\/p>\n\n <table class=\"wrapok\">\n <caption>Long-duration & gold-standard-method kidney studies (independent groups unless noted)<\/caption>\n <thead><tr><th>Study<\/th><th>Population & exposure<\/th><th>Method<\/th><th>Result<\/th><\/tr><\/thead>\n <tbody>\n <tr><td class=\"tnum\">Poortmans & Francaux 1999 IND<\/span><\/td><td>Healthy athletes, creatine use 10 months \u2013 5 years<\/strong> vs controls<\/td><td>Creatinine, urea & albumin clearances<\/td><td class=\"good\">No differences in GFR, tubular reabsorption, or membrane permeability \u2014 the foundational long-term dataset (limits: retrospective, non-randomized)<\/td><\/tr>\n <tr><td class=\"tnum\">Kreider et al. 2003 ISSN<\/span><\/td><td>College athletes, up to 21 months<\/strong>, ~5\u201310 g\/d<\/td><td>69 clinical health markers<\/td><td class=\"good\">No significant differences vs non-users<\/td><\/tr>\n <tr><td class=\"tnum\">Gualano et al. 2008 IND \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Healthy adults, 12 wk, ~10 g\/d, RCT<\/td><td>Cystatin C<\/strong> (creatinine-independent)<\/td><td class=\"good\">Cystatin C unchanged (actually slightly decreased) \u2014 no injury<\/td><\/tr>\n <tr><td class=\"tnum\">Lugaresi et al. 2013 IND \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Resistance-trained adults on a high-protein diet<\/strong> (\u22651.2 g\/kg\/d), 12 wk, 20\u21925 g\/d, RCT<\/td><td>\u2075\u00b9Cr-EDTA clearance<\/strong> (tracer gold standard)<\/td><td class=\"good\">No change in measured GFR \u2014 the \u201ccreatine + high protein wrecks kidneys\u201d stack claim fails its direct test<\/td><\/tr>\n <tr><td class=\"tnum\">Gualano et al. 2011 IND<\/span><\/td><td>Type 2 diabetics<\/strong> (renally vulnerable), 12 wk, RCT<\/td><td>\u2075\u00b9Cr-EDTA clearance<\/td><td class=\"good\">No impairment<\/td><\/tr>\n <tr><td class=\"tnum\">Neves et al. 2011 IND<\/span><\/td><td>Postmenopausal women<\/strong>, RCT<\/td><td>Measured GFR<\/td><td class=\"good\">No effect \u2014 female-specific renal reassurance<\/td><\/tr>\n <tr><td class=\"tnum\">Bender et al. 2008 IND<\/span><\/td><td>Parkinson\u2019s patients, 2 years<\/strong>, 4 g\/d, placebo-controlled<\/td><td>Renal markers incl. cystatin C<\/td><td class=\"good\">No significant changes after 2 years of continuous use<\/td><\/tr>\n <tr><td class=\"tnum\">Gualano et al. 2010 IND<\/span><\/td><td>Young man with a single kidney<\/strong> and mildly reduced GFR, 35 d, 20\u21925 g\/d<\/td><td>Measured GFR<\/td><td class=\"mid\">Case study: GFR unchanged \u2014 reassuring but n=1, not generalizable<\/td><\/tr>\n <tr><td class=\"tnum\">Hemodialysis subgroup, 2026 meta IND<\/span><\/td><td>Dialysis patients (kidneys already failed)<\/td><td>Pooled RCT markers<\/td><td class=\"mid\">Serum creatinine rose (expected); serum urea fell<\/em>; no injury signal \u2014 but this is therapy research, not license for CKD self-supplementation<\/td><\/tr>\n <tr><td class=\"tnum\">Longobardi et al. 2023 IND<\/span><\/td><td>Narrative review, \u201crequiem for creatine-induced kidney failure?\u201d<\/td><td>All case reports re-examined<\/td><td class=\"good\">Nearly every published \u201ccreatine kidney failure\u201d case involved confounders: pre-existing disease, anabolic steroids, NSAIDs, dehydration protocols, or unverified multi-ingredient products<\/td><\/tr>\n <\/tbody>\n <\/table>\n Long-term verdict, stated plainly:<\/strong> at 3\u201310 g\/day, across every controlled study up to 2 years and observational use to 5 years, chronic intake has not damaged healthy kidneys by any creatinine-independent measure. What long-term intake does<\/em> do, permanently while you take it, is elevate serum creatinine \u2014 a lab artifact that will follow you into every routine blood panel. The remaining unknowns are pre-existing CKD stages 1\u20135 (zero long-term RCTs \u2014 the 2026 meta-analysis authors note this gap explicitly) and unsupervised decades-scale use. If you have one kidney, reduced GFR, diabetes with nephropathy, or take nephrotoxic drugs (NSAIDs chronically, some antibiotics), supplement only with physician monitoring.<\/p>\n<\/section>\n\n<section id=\"water\">\n Water<\/span>\n <h2>\u201cDrink gallons or you\u2019ll dehydrate\u201d is backwards<\/h2>\n The osmotic logic is real but points the opposite direction from the myth. Creatine pulls water into<\/strong> muscle cells: loading (20 g\/day) measurably raises total and intracellular body water for days, which is most of the famous 1\u20132 kg scale jump. Over 5\u201310-week training studies, total body water relative to muscle mass<\/em> shows no lasting distortion. On dehydration and cramping \u2014 a belief once endorsed even by the ACSM in the early 2000s on speculation, not data \u2014 the controlled literature finds no causation, and several heat-stress studies found creatine users had lower core temperatures and better fluid retention<\/strong> than placebo; older athlete cohorts reported cramping reduced, not increased. The Brazilian (Gualano-group) 2025 safety review in Frontiers in Nutrition<\/i> concludes hydration and thermoregulation are unaffected.<\/p>\n <div class=\"callout blue\">\n Practical translation<\/span>\n Normal thirst-guided fluid intake suffices. The \u201cgallon rule\u201d is folklore; forced water-loading has no evidence base and its only reliable effect is inconvenience. The intracellular water shift is also why first-week scale weight is meaningless as a muscle measure \u2014 see Fig. 3.<\/p>\n <\/div>\n<\/section>\n\n<section id=\"liver\">\n Liver<\/span>\n <h2>Liver: no credible harm signal \u2014 and an inverted association<\/h2>\n No meta-analysis or long-term trial detects hepatotoxicity at studied doses. Dedicated hepatic-marker meta-analyses (Alizadeh 2022, Sports Medicine \u2013 Open<\/i>; Kashi 2024, Nutrition Research Reviews<\/i>) find liver enzymes unchanged; a 52-week trial at 5 g\/day in older adults kept enzymes stable; adolescent and youth-athlete cohorts through full competitive seasons kept ALT\/AST within reference ranges with no hepatotoxicity signal META<\/span> RCT<\/span>. The inversion worth reporting: NHANES analyses associate low dietary<\/em> creatine (<0.95\u20131 g\/day) with higher<\/em> risk of liver conditions \u2014 observational only COHORT<\/span>, meat-intake-confounded, but it flips the folk narrative. The honest gap: people with existing liver disease are nearly absent from trials; since the liver hosts the GAMT step of synthesis, severe hepatic impairment is a legitimate reason for medical supervision, not a documented creatine harm.<\/p>\n<\/section>\n\n<section id=\"skin\">\n Skin \u2014 commercial corner<\/span>\n <h2>Skin: the weakest, most industry-owned claim in the file<\/h2>\n This is where the independent-versus-commercial filter matters most. The frequently cited anti-wrinkle findings come from topical cosmetic formulations studied largely by Beiersdorf (Nivea) scientists<\/strong>: a single-centre controlled study of 43 men applying a cream containing creatine plus guarana and glycerol<\/em> reported firmness and wrinkle improvements at six weeks (Peirano 2011, J Cosmetic Dermatology<\/i>) COMMERCIAL<\/span>; earlier in-house work reported photoprotection and stimulated collagen, glycosaminoglycan and ceramide synthesis (Lenz 2005) COMMERCIAL<\/span>. Mechanistically plausible \u2014 skin\u2019s creatine-kinase energy system genuinely declines with age and oxidative stress \u2014 but these are multi-ingredient, industry-run, single-centre studies, never independently replicated at scale.<\/p>\n <div class=\"callout amber\">\n Verdict<\/span>\n Oral creatine for skin: unproven.<\/strong> There is no direct evidence that 3\u20135 g\/day orally produces measurable changes in skin quality \u2014 every clinical result comes from creams and serums. Topical creatine: low-certainty, commercially generated Tier 4 evidence.<\/strong> Claims of \u201ccreatine causes acne\u201d are equally unsupported in either direction. If skin is the goal, the evidence-backed money goes to photoprotection and retinoids, not creatine.<\/p>\n <\/div>\n<\/section>\n\n<section id=\"brain\">\n Brain, cognition & mood<\/span>\n <h2>The strongest genuinely new post-2015 story<\/h2>\n The brain burns ~20% of the body\u2019s energy at 2% of its mass, and brain creatine \u2014 unlike muscle \u2014 responds slowly and modestly to supplementation. The most striking independent finding comes from a German government research institute (Forschungszentrum J\u00fclich): in a randomized double-blind crossover trial, a single oral dose of 0.35 g\/kg<\/strong> during 21 hours of sleep deprivation raised brain PCr\/Pi, prevented a pH drop, and improved cognitive performance and processing speed \u2014 partially reversing fatigue-related deterioration (Gordji-Nejad 2024, Scientific Reports<\/i>, n=15) RCT<\/span> INDEPENDENT<\/span>. A 2026 replication at a lower 0.2 g\/kg<\/strong> dose (n=29) still mitigated deterioration in logic, numerical tasks, language-processing speed and psychomotor vigilance \u2014 with the authors noting the short-term-memory effect appears dose-dependent.<\/p>\n\n <figure aria-label=\"Cognition meta-analysis forest-style chart\">\n <svg viewBox=\"0 0 940 380\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Meta-analytic effects of creatine on cognitive domains<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">COGNITIVE DOMAINS \u2014 16 RCTs, n=492, ages 20.8\u201376.4 (Xu 2024, Frontiers in Nutrition)<\/text>\n <text x=\"30\" y=\"52\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">standardised mean difference; bars scaled |SMD| \u2014 negative time scores = faster = benefit<\/text>\n\n <line x1=\"360\" y1=\"80\" x2=\"360\" y2=\"330\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <text x=\"360\" y=\"350\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">0<\/text>\n\n <text x=\"40\" y=\"112\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Memory<\/text>\n <rect x=\"360\" y=\"94\" width=\"124\" height=\"30\" fill=\"#093644\"\/>\n <text x=\"494\" y=\"115\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#0C3A4D\">SMD +0.31 (0.18\u20130.44) \u2014 significant<\/text>\n\n <text x=\"40\" y=\"172\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Attention time<\/text>\n <rect x=\"360\" y=\"154\" width=\"124\" height=\"30\" fill=\"#14556E\"\/>\n <text x=\"494\" y=\"175\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#14556E\">SMD \u22120.31 (\u22120.58 to \u22120.03) \u2014 faster<\/text>\n\n <text x=\"40\" y=\"232\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Processing speed<\/text>\n <rect x=\"360\" y=\"214\" width=\"204\" height=\"30\" fill=\"#14556E\"\/>\n <text x=\"574\" y=\"235\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#14556E\">SMD \u22120.51 (\u22121.01 to \u22120.01) \u2014 faster, wide CI<\/text>\n\n <text x=\"40\" y=\"292\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Overall cognition \u00b7 executive function<\/text>\n <rect x=\"352\" y=\"274\" width=\"16\" height=\"30\" fill=\"#96600B\"\/>\n <text x=\"380\" y=\"295\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#96600B\">not significant \u2014 no global IQ effect<\/text>\n <\/svg>\n <figcaption>Fig. 5 \u2014 Small, domain-specific, condition-dependent.<\/b> Effects concentrate where brain energy supply is strained: sleep deprivation, vegetarians\/vegans (lowest baseline stores, largest gains since Rae 2003), older adults, heavy mental fatigue. In rested young omnivores the system is near-saturated and effects approach zero. Depression: several small RCTs of 3\u20135 g\/day added to SSRIs show faster, larger improvement \u2014 most consistently in women \u2014 Tier 3 emerging, not yet definitive.<\/figcaption>\n <\/figure>\n<\/section>\n\n<section id=\"women\">\n Women\u2019s health<\/span>\n <h2>Women: real physiology, thinner evidence than the headlines imply<\/h2>\n The physiology is distinct and understudied: females carry 70\u201380% lower<\/span> endogenous creatine stores than males yet ~10% higher<\/em> resting intramuscular concentrations, and estrogen\/progesterone modulate AGAT\/GAMT expression and creatine-kinase kinetics across the menstrual cycle, pregnancy and menopause (Smith-Ryan 2021; Ellery 2016). That makes supplementation plausibly more<\/em> relevant at specific life stages \u2014 and also makes early performance studies that ignored cycle phase harder to interpret.<\/p>\n\n <figure aria-label=\"Women's lifespan evidence map\">\n <svg viewBox=\"0 0 940 330\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Evidence strength for creatine across the female lifespan<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">EVIDENCE ACROSS THE FEMALE LIFESPAN \u2014 colour = certainty tier<\/text>\n\n \n <line x1=\"60\" y1=\"230\" x2=\"900\" y2=\"230\" stroke=\"#16232B\" stroke-width=\"2\"\/>\n\n \n <rect x=\"60\" y=\"90\" width=\"200\" height=\"120\" fill=\"#14556E\" rx=\"3\"\/>\n <text x=\"160\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">MENSTRUATING YEARS<\/text>\n <text x=\"160\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#DCE7EC\">strength & performance \u2191<\/text>\n <text x=\"160\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#DCE7EC\">with training \u00b7 TIER 2<\/text>\n <text x=\"160\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#B9CDD6\">cycle-controlled trials only recent<\/text>\n\n \n <rect x=\"280\" y=\"90\" width=\"190\" height=\"120\" fill=\"#A63525\" rx=\"3\"\/>\n <text x=\"375\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">PREGNANCY<\/text>\n <text x=\"375\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F4DEDA\">mostly animal models<\/text>\n <text x=\"375\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F4DEDA\">no human RCTs \u00b7 TIER 4\/5<\/text>\n <text x=\"375\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#F4DEDA\">DO NOT EXTRAPOLATE<\/text>\n\n \n <rect x=\"490\" y=\"90\" width=\"190\" height=\"120\" fill=\"#96600B\" rx=\"3\"\/>\n <text x=\"585\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">PERIMENOPAUSE<\/text>\n <text x=\"585\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F3E7D2\">near-empty evidence zone<\/text>\n <text x=\"585\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F3E7D2\">first small trials 2025 \u00b7 TIER 3\/4<\/text>\n <text x=\"585\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#F3E7D2\">sleep-quality signal, n=15<\/text>\n\n \n <rect x=\"700\" y=\"90\" width=\"200\" height=\"120\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"800\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">POST-MENOPAUSE<\/text>\n <text x=\"800\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#E4E9EC\">muscle size\/function at high<\/text>\n <text x=\"800\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#E4E9EC\">dose 0.3 g\/kg\/d + training<\/text>\n <text x=\"800\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#E4E9EC\">bone: mixed \u00b7 TIER 2\/3<\/text>\n\n \n <rect x=\"60\" y=\"252\" width=\"840\" height=\"46\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"480\" y=\"272\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">FEMALE-SPECIFIC SAFETY META-ANALYSIS (de Guingand 2020 \u00b7 29 monitored studies \u00b7 n=951)<\/text>\n <text x=\"480\" y=\"290\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">no deaths or serious adverse outcomes \u00b7 total AEs RR 1.24 (0.51\u20132.98) n.s. \u00b7 GI RR 1.09 n.s. \u00b7 weight gain n.s.<\/text>\n <\/svg>\n <figcaption>Fig. 6 \u2014 The female evidence map.<\/b> Sources: Smith-Ryan et al. 2021 & 2025 (lifespan reviews \u2014 ISSN-cluster authorship, flagged), Hall 2025 (peri\/post-menopause quasi-experimental, n=15: lower-body strength \u2191, perimenopausal sleep quality p=0.0181, estradiol unchanged), CONCRET-MENOPA RCT 2025 (n=36: 1.5 g\/day creatine HCl improved reaction time and raised frontal brain creatine +16.4% vs 0.9% placebo), de Guingand 2020 safety meta-analysis (independent, Hudson Institute). Only 9% of all creatine studies to 2020 were female-only.<\/figcaption>\n <\/figure>\n\n <h3>The women\u2019s trial base, paper by paper<\/h3>\n Because the headlines outrun the trials here, the substantive female-specific studies located in this pass are tabulated below. Two things stand out. First, the two largest and longest<\/strong> women\u2019s trials ever run \u2014 both independent \u2014 were bone<\/em> trials, and both were essentially null on bone density. Second, the most consistent positive female-specific signal is not muscle at all: it is depression augmentation and brain energetics<\/strong>, from an independent psychiatry group (Univ. of Utah \/ Seoul) with no supplement-industry stake.<\/p>\n\n <table class=\"wrapok\">\n <caption>Female-specific studies \u2014 design, size, outcome<\/caption>\n <thead><tr><th>Study<\/th><th>Design & population<\/th><th>Dose \/ duration<\/th><th>Outcome<\/th><\/tr><\/thead>\n <tbody>\n <tr><td class=\"tnum\">Chilibeck 2015 IND<\/span><\/td><td>RCT, postmenopausal women + supervised resistance training<\/td><td class=\"tnum\">0.1 g\/kg\/d \u00b7 12 mo<\/td><td class=\"mid\">Femoral-neck BMD loss slowed<\/em> vs placebo \u2014 the hopeful signal that motivated the bigger trial<\/td><\/tr>\n <tr><td class=\"tnum\">Chilibeck 2023 IND<\/span><\/td><td>RCT, n=237<\/strong> postmenopausal women, training + walking, 2 years<\/strong> \u2014 the largest women\u2019s creatine trial ever run<\/td><td class=\"tnum\">0.14 g\/kg\/d (~9.8 g) \u00b7 24 mo<\/td><td class=\"mid\">BMD: null<\/strong> at femoral neck, total hip, lumbar spine. Positive secondaries: femoral-neck section modulus preserved (p=0.0011), buckling ratio improved (p=0.011), 80-m walk faster (p=0.0008), lean mass +1.1 kg in completers. Strength (1RM): no difference<\/td><\/tr>\n <tr><td class=\"tnum\">Sales\/Gualano 2020 IND \u2014 S\u00e3o Paulo<\/span><\/td><td>RCT, n=200<\/strong> postmenopausal women with osteopenia, 2 years<\/strong>, no structured training<\/td><td class=\"tnum\">3 g\/d \u00b7 24 mo<\/td><td class=\"bad\">Null on BMD, bone markers, microarchitecture, falls\/fractures \u2014 and null on lean mass and muscle function<\/em>. Authors: \u201crefutes the long-lasting notion that this supplement alone has osteogenic or anabolic properties.\u201d Safety labs clean throughout<\/td><\/tr>\n <tr><td class=\"tnum\">Postmenopausal meta 2025 IND<\/span><\/td><td>Systematic review + meta-analysis, 2000\u2013Aug 2025, RCTs in women \u226540\u201345<\/td><td class=\"tnum\">various \u22656 wk<\/td><td class=\"mid\">Lean mass pooled +0.37 kg<\/strong>; BMD pooled MD \u2248 0.00 g\/cm\u00b2 \u2014 CIs span no-effect throughout<\/td><\/tr>\n <tr><td class=\"tnum\">Lyoo 2012 IND \u2014 psychiatry<\/span><\/td><td>Double-blind RCT, n=52 women<\/strong> with major depressive disorder, creatine added to escitalopram<\/td><td class=\"tnum\">3\u21925 g\/d \u00b7 8 wk<\/td><td class=\"good\">Faster, larger HAM-D improvement vs SSRI+placebo (reported effect size ~d=1.13); more remissions; good tolerability<\/td><\/tr>\n <tr><td class=\"tnum\">Yoon 2015 IND<\/span><\/td><td>Neuroimaging arm of the same RCT, n=34<\/td><td class=\"tnum\">5 g\/d \u00b7 8 wk<\/td><td class=\"good\">Prefrontal NAA increased vs placebo (d=0.73); rich-club network connectivity normalized \u2014 a mechanism, not just a rating scale<\/td><\/tr>\n <tr><td class=\"tnum\">Kondo 2016 IND \u2014 NIMH-funded<\/span><\/td><td>Dose-ranging RCT, n=33 adolescent females<\/strong>, SSRI-resistant depression<\/td><td class=\"tnum\">2 \/ 4 \/ 10 g\/d \u00b7 8 wk<\/td><td class=\"mid\">Depression scores: no significant difference vs placebo<\/strong>; but brain phosphocreatine rose dose-dependently and correlated with mood improvement \u2014 target engaged, clinical effect unproven in teens<\/td><\/tr>\n <tr><td class=\"tnum\">Hall 2025 IND<\/span><\/td><td>Quasi-experimental, n=15 peri\/postmenopausal + training, 14 wk<\/td><td class=\"tnum\">std dose<\/td><td class=\"mid\">Lower-body strength \u2191; perimenopausal sleep quality \u2191 (p=0.0181); estradiol unchanged \u2014 tiny, non-randomized<\/td><\/tr>\n <tr><td class=\"tnum\">CONCRET-MENOPA 2025 ISSN<\/span><\/td><td>RCT, n=36 peri\/menopausal women<\/td><td class=\"tnum\">0.75\u20131.5 g\/d HCl \u00b7 8 wk<\/td><td class=\"mid\">Reaction time \u2191, frontal brain creatine +16.4% vs 0.9%, lipids improved \u2014 small, non-monohydrate forms<\/td><\/tr>\n <tr><td class=\"tnum\">de Guingand 2020 IND \u2014 Hudson Inst.<\/span><\/td><td>Safety meta-analysis, 29 monitored female-only studies, n=951<\/td><td class=\"tnum\">all doses<\/td><td class=\"good\">No deaths or serious adverse outcomes; total AEs, GI events, weight gain all non-significant vs placebo<\/td><\/tr>\n <tr><td class=\"tnum\">Gordon 2023 ISSN<\/span><\/td><td>Crossover RCT, n=39 active women, both cycle phases<\/td><td class=\"tnum\">20 g\/d loading<\/td><td class=\"mid\">No HRV harm; recovery effects modest; first properly cycle-controlled loading study<\/td><\/tr>\n <tr><td class=\"tnum\">Dickinson 2016 IND<\/span><\/td><td>Retrospective pregnancy cohort, n=287<\/strong><\/td><td class=\"tnum\">dietary only<\/td><td class=\"mid\">Higher maternal urinary creatine associated with higher birthweight centile (+1.23\/\u03bcmol\u00b7L\u207b\u00b9) and birth length \u2014 associational<\/td><\/tr>\n <tr><td class=\"tnum\">de Guingand 2024 (CPO) IND<\/span><\/td><td>Prospective pregnancy cohort, n=282<\/strong>, 5 timepoints + cord\/placenta<\/td><td class=\"tnum\">dietary only<\/td><td class=\"good\">Plasma creatine stable across gestation; synthesis machinery visibly reorganizes (GAA shifts); animal-protein intake tracks plasma creatine; no adverse creatine\u2013growth links<\/td><\/tr>\n <tr><td class=\"tnum\">Naidu 2025 IND \u2014 Monash<\/span><\/td><td>Open-label dose-escalation PK trial, third-trimester women (n=15 total)<\/td><td class=\"tnum\">5 g \u00d71, then 5 g q8h \u00d73 d<\/td><td class=\"mid\">First human supplementation-in-pregnancy data: well tolerated short-term, PK characterized, fetal monitoring unremarkable \u2014 a phase-1-style step, not<\/strong> an efficacy or safety endorsement<\/td><\/tr>\n <tr><td class=\"tnum\">Freeman 2025 IND \u2014 Otago<\/span><\/td><td>Guinea-pig full-term pregnancy safety model<\/td><td class=\"tnum\">0.3 g\/kg\/d<\/td><td class=\"mid\">No fetal-growth or offspring harm \u2014 preclinical, supports proceeding to trials, nothing more<\/td><\/tr>\n <\/tbody>\n <\/table>\n\n Reading that table honestly: for bone<\/strong>, the two independent 2-year RCTs (437 women combined) say creatine does not raise bone mineral density \u2014 at most it preserves some geometry of the femoral neck when combined with training (Chilibeck) and does nothing without training (S\u00e3o Paulo). For muscle<\/strong>, the effect in women is real but small (+0.37 kg pooled lean mass) and appears to require training. For mood and brain<\/strong>, women are where creatine\u2019s most interesting clinical signal lives \u2014 plausibly because of the 70\u201380% lower baseline stores \u2014 but the total randomized evidence is a few hundred participants, with the adolescent trial null on symptoms. For pregnancy<\/strong>, human work has only just reached pharmacokinetics; every efficacy claim you may read is extrapolated from spiny-mouse and guinea-pig models.<\/p>\n\n Challenge to the popular beliefs:<\/strong> \u201ccreatine makes women bulky\u201d fails twice \u2014 women\u2019s hormonal milieu limits hypertrophy, and the UNSW sex-disaggregated data showed women\u2019s early scale gain was the fluid<\/em> component with no added muscle growth thereafter. But the mirror-image marketing claim \u2014 creatine as a proven menopause therapy \u2014 also overreaches: the peri-menopause trials are tiny (n=15\u201336), weeks long, and partly non-randomized. Real signal, Tier 3, worth watching, not yet worth prescribing.<\/p>\n<\/section>\n\n<section id=\"men\">\n Men\u2019s health<\/span>\n <h2>Hair, DHT and testosterone: one study built the myth, one finally tested it<\/h2>\n The hair-loss belief traces to exactly one trial: 2009, college rugby players, three weeks, reporting a +56%<\/span> DHT rise after loading. It was never replicated \u2014 twelve subsequent studies on testosterone and its metabolites found no significant hormonal increases. In 2025 the first direct<\/em> test arrived: a 12-week RCT in 45 resistance-trained men (5 g\/day vs maltodextrin placebo) measuring hormones and actual hair-follicle outcomes<\/strong> found no group differences in DHT, DHT-to-testosterone ratio, or any hair-growth parameter \u2014 the authors call it strong evidence against the claim (Lak 2025, JISSN<\/i>).<\/p>\n\n <figure aria-label=\"DHT myth provenance chart\">\n <svg viewBox=\"0 0 940 300\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Provenance of the DHT and hair loss myth versus the 2025 direct test<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">ANATOMY OF A MYTH \u2014 the entire DHT\/hair-loss evidence base<\/text>\n\n \n <rect x=\"40\" y=\"60\" width=\"260\" height=\"160\" fill=\"#A63525\" rx=\"3\"\/>\n <text x=\"170\" y=\"90\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">2009 \u00b7 van der Merwe<\/text>\n <text x=\"170\" y=\"114\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">rugby players \u00b7 3 weeks<\/text>\n <text x=\"170\" y=\"134\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">DHT +56% after loading<\/text>\n <text x=\"170\" y=\"158\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">hair NEVER measured<\/text>\n <text x=\"170\" y=\"182\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">never replicated<\/text>\n <text x=\"170\" y=\"206\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"11.5\" fill=\"#FFFFFF\">n = 20 \u00b7 one study<\/text>\n\n \n <rect x=\"340\" y=\"60\" width=\"260\" height=\"160\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"470\" y=\"90\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">2009\u20132024 \u00b7 12 studies<\/text>\n <text x=\"470\" y=\"118\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#E4E9EC\">total, free testosterone<\/text>\n <text x=\"470\" y=\"138\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#E4E9EC\">& metabolites examined<\/text>\n <text x=\"470\" y=\"166\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">no significant hormonal<\/text>\n <text x=\"470\" y=\"186\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">increases found<\/text>\n\n \n <rect x=\"640\" y=\"60\" width=\"260\" height=\"160\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"770\" y=\"90\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">2025 \u00b7 Lak \u2014 direct test<\/text>\n <text x=\"770\" y=\"114\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">RCT \u00b7 12 wk \u00b7 n=45 \u00b7 5 g\/d<\/text>\n <text x=\"770\" y=\"138\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">DHT: no difference<\/text>\n <text x=\"770\" y=\"158\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">DHT:T ratio: no difference<\/text>\n <text x=\"770\" y=\"178\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">hair-growth parameters:<\/text>\n <text x=\"770\" y=\"198\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">no difference vs placebo<\/text>\n\n <text x=\"30\" y=\"262\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">Caveat kept honest: the 2025 trial includes ISSN-cluster co-authors \u2014 but it is the only direct hair-follicle evidence either way, and it agrees<\/text>\n <text x=\"30\" y=\"280\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">with twelve independent hormone datasets. Creatine is not androgenic and is not chemically or legally a steroid.<\/text>\n <\/svg>\n <figcaption>Fig. 7 \u2014 One unreplicated n=20 study versus the rest of the literature.<\/b> For men with strong family-history androgenic alopecia the theoretical residual risk cannot be reduced to exactly zero, but no measured pathway supports it. Fertility: creatine is concentrated in testes and sperm; small studies suggest neutral-to-positive effects on sperm energetics \u2014 Tier 3\/4, insufficient for claims.<\/figcaption>\n <\/figure>\n<\/section>\n<section id=\"interactions\">\n Co-ingestion & interactions<\/span>\n <h2>Taking creatine with other nutrients, supplements \u2014 and water<\/h2>\n The direct answer to \u201cwill taking it with other macro\/micronutrients or supplements damage me or be unhealthy?\u201d is: no harmful nutrient\u2013creatine interaction has been documented in the controlled literature.<\/strong> The known interactions all concern uptake and effectiveness<\/em>, not safety. The one practical safety issue is not an interaction at all \u2014 it is product purity: multi-ingredient pre-workouts with unverified formulations are the setting where most real-world adverse-event reports arise, which is why plain third-party-tested monohydrate is the defensible choice.<\/p>\n\n <table class=\"wrapok\">\n <caption>Co-ingestion evidence \u2014 effect on uptake, performance, and safety<\/caption>\n <thead><tr><th>Combined with<\/th><th>What the evidence shows<\/th><th>Safety concern?<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>Carbohydrates<\/strong><\/td><td>Insulin drives the muscle creatine transporter (SLC6A8, PI3K\/Akt pathway, analogous to GLUT4). Classic Green\/Steenge work: large carbohydrate doses (~93 g) raised muscle creatine retention substantially; ~50 g carbohydrate + ~50 g protein reproduced the effect with less sugar. Practically: taking creatine with a normal meal captures most of this; chasing it with ~370 g\/day of sugar during loading (as in the original protocols) is unnecessary and its calorie load is the only \u201charm.\u201d<\/td><td class=\"good\">None \u2014 synergistic for uptake<\/td><\/tr>\n <tr><td>Protein \/ amino acids<\/strong><\/td><td>Protein is insulinotropic; co-ingestion enhances retention roughly additively with carbohydrate. The Lugaresi \u2075\u00b9Cr-EDTA trial specifically tested creatine on top of a high-protein diet<\/em> (\u22651.2 g\/kg\/d) and found no kidney harm by tracer-measured GFR \u2014 the popular \u201cprotein + creatine double-taxes the kidneys\u201d claim fails its direct test.<\/td><td class=\"good\">None, including renally<\/td><\/tr>\n <tr><td>Caffeine \/ coffee<\/strong><\/td><td>The one genuinely debated interaction \u2014 about effectiveness<\/em>, not safety. A 1996 study suggested chronic high-dose caffeine (5 mg\/kg) during creatine loading blunted creatine\u2019s ergogenic effect, possibly via opposing muscle-relaxation effects; pharmacokinetics are unaffected (Vanakoski). The 2022 systematic review (Elosegui, 10 studies): acute caffeine after creatine loading works fine and is often synergistic; chronic simultaneous high-dose co-ingestion showed interference in 2 studies, no interaction in 3, synergy in 1. Ordinary coffee (1\u20133 cups) is far below the doses in question. Some people get GI upset taking both at once.<\/td><td class=\"mid\">No health harm; possible ergogenic blunting at high chronic doses \u2014 unresolved<\/td><\/tr>\n <tr><td>\u03b2-alanine<\/strong><\/td><td>2025 systematic review (7 RCTs, n=263): co-supplementation adds little beyond each supplement alone; inconsistent synergy; no added adverse events.<\/td><td class=\"good\">None<\/td><\/tr>\n <tr><td>Micronutrients (vitamin D, calcium, iron\u2026)<\/strong><\/td><td>No documented adverse interactions. Emerging (weak) evidence that vitamin D status may modulate creatine-transporter expression. Creatine does not deplete or block any vitamin or mineral; conversely it spares<\/em> methionine\/SAMe, glycine and arginine by down-regulating endogenous synthesis.<\/td><td class=\"good\">None documented<\/td><\/tr>\n <tr><td>Medications<\/strong><\/td><td>The real-world flags: chronic NSAIDs, nephrotoxic antibiotics, or diuretics in people with reduced kidney function \u2014 not because creatine injures the kidney, but because these settings need clean renal monitoring, which creatine\u2019s creatinine artifact muddies. SSRI co-use appears safe and is the basis of the depression trials. Anyone on prescription drugs affecting kidneys or fluid balance should tell their physician.<\/td><td class=\"mid\">Monitoring issue, not toxicity<\/td><\/tr>\n <tr><td>Multi-ingredient pre-workouts<\/strong><\/td><td>Where adverse-event reports cluster: unverified doses, proprietary blends, stimulant stacking, contamination. In the 28.4-million-report surveillance analysis, half of \u201ccreatine\u201d reports involved products where creatine wasn\u2019t even a listed ingredient.<\/td><td class=\"bad\">The genuine real-world risk \u2014 use plain tested monohydrate instead<\/td><\/tr>\n <tr><td>Water<\/strong><\/td><td>Creatine is osmotically active and shifts ~0.5\u20131 L into the intracellular compartment during saturation. Controlled studies show no dehydration, no impaired thermoregulation, lower core temperatures in heat, and reduced cramping in athlete cohorts. Thirst-guided normal drinking is sufficient; the \u201cgallon rule\u201d has no evidence base. The only water-related realities: expect 1\u20132 kg scale weight from intracellular water, and take powder dissolved in enough fluid (~250\u2013500 mL) to avoid GI upset from large boluses.<\/td><td class=\"good\">None \u2014 the myth runs backwards<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"dose\">\n Dose, overdose & long exposure<\/span>\n <h2>How much is too much? Less alarming \u2014 and less magical \u2014 than believed<\/h2>\n There is no documented lethal or organ-toxic oral dose of creatine monohydrate in humans; the practical ceiling is gastrointestinal. Above muscle saturation (reached by ~3\u20135 g\/day within 3\u20134 weeks, or 20 g\/day for 5\u20137 days), excess creatine is simply excreted unchanged in urine<\/strong> \u2014 expensive urine, not toxicity. The largest safety dataset ever compiled pooled 685 clinical trials<\/span>: 12,839 participants on creatine (average ~12.5 g\/day, durations to 14 years) versus 13,452 on placebo.<\/p>\n\n <figure aria-label=\"Side effects creatine versus placebo\">\n <svg viewBox=\"0 0 940 340\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Side-effect prevalence, creatine versus placebo, across 685 trials<\/title>\n <text x=\"30\" y=\"26\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">SIDE-EFFECT REPORTING ACROSS 685 TRIALS<\/text>\n <text x=\"30\" y=\"46\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#16232B\">(Kreider 2025 \u2014 dataset = all published RCTs; authorship ISSN-cluster, flagged)<\/text>\n\n \n <line x1=\"120\" y1=\"260\" x2=\"880\" y2=\"260\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n\n \n <text x=\"240\" y=\"70\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Studies reporting any side effect<\/text>\n \n <rect x=\"160\" y=\"128\" width=\"70\" height=\"132\" fill=\"#7E8D96\"\/>\n <text x=\"195\" y=\"118\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#4A5B66\">13.2%<\/text>\n <text x=\"195\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">placebo<\/text>\n \n <rect x=\"250\" y=\"123\" width=\"70\" height=\"137\" fill=\"#093644\"\/>\n <text x=\"285\" y=\"113\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#0C3A4D\">13.7%<\/text>\n <text x=\"285\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#0C3A4D\">creatine<\/text>\n <text x=\"240\" y=\"308\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">p = 0.776 \u2014 indistinguishable<\/text>\n\n \n <text x=\"600\" y=\"70\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Participants reporting side effects<\/text>\n \n <rect x=\"520\" y=\"218\" width=\"70\" height=\"42\" fill=\"#7E8D96\"\/>\n <text x=\"555\" y=\"208\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#4A5B66\">4.21%<\/text>\n <text x=\"555\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">placebo<\/text>\n \n <rect x=\"610\" y=\"214\" width=\"70\" height=\"46\" fill=\"#093644\"\/>\n <text x=\"645\" y=\"204\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#0C3A4D\">4.60%<\/text>\n <text x=\"645\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#0C3A4D\">creatine<\/text>\n <text x=\"600\" y=\"308\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">p = 0.828 \u2014 indistinguishable<\/text>\n\n <text x=\"700\" y=\"130\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">2026 dose\u2013response analysis,<\/text>\n <text x=\"700\" y=\"148\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">684 RCTs: no dose- or duration-<\/text>\n <text x=\"700\" y=\"166\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">dependent risk increase; placebo<\/text>\n <text x=\"700\" y=\"184\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">groups often reported MORE.<\/text>\n <\/svg>\n <figcaption>Fig. 8 \u2014 \u201cOverdose\u201d in the trial record.<\/b> The one reproducible dose-dependent effect is GI upset at loading-size single boluses (\u226510\u201320 g at once) \u2014 solved by splitting doses or skipping loading entirely. Global adverse-event surveillance: creatine appears in 0.00072% of 28.4 million reports, and in nearly half of those it was not even a listed ingredient. Genuinely unknown territory that keeps this out of Tier-1 blanket status: pre-existing CKD, pregnancy, and >10 g\/day sustained for years unsupervised.<\/figcaption>\n <\/figure>\n\n <table class=\"wrapok\">\n <caption>Dosing protocols \u2014 what the evidence supports<\/caption>\n <thead><tr><th>Protocol<\/th><th>Dose<\/th><th>Time to saturation<\/th><th>Evidence note<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>Maintenance (standard)<\/td><td class=\"tnum\">3\u20135 g\/day (or 0.1 g\/kg\/day)<\/td><td class=\"tnum\">3\u20134 weeks<\/td><td class=\"good\">Same end-state as loading; fewest GI complaints; the default<\/td><\/tr>\n <tr><td>Loading (optional)<\/td><td class=\"tnum\">20 g\/day in 4\u00d75 g, 5\u20137 days<\/td><td class=\"tnum\">~1 week<\/td><td class=\"mid\">Faster only; \u201cmust load\u201d is folklore \u2014 loading is never mandatory<\/td><\/tr>\n <tr><td>Post-menopause muscle protocols<\/td><td class=\"tnum\">0.3 g\/kg\/day (high)<\/td><td class=\"tnum\">\u2014<\/td><td class=\"mid\">Used in Chilibeck-line trials; Tier 2\/3 with training<\/td><\/tr>\n <tr><td>Brain \/ sleep-deprivation rescue<\/td><td class=\"tnum\">single 0.2\u20130.35 g\/kg<\/td><td class=\"tnum\">acute (3\u20137.5 h)<\/td><td class=\"mid\">Two small crossover RCTs; proof of concept, not routine advice<\/td><\/tr>\n <tr><td>Hypertrophy beyond training<\/td><td class=\"tnum\">~10 g\/day (proposed)<\/td><td class=\"tnum\">\u2014<\/td><td class=\"bad\">Suggested by UNSW authors after their 5 g null; untested in a dedicated RCT<\/td><\/tr>\n <tr><td>Form<\/td><td colspan=\"3\">Creatine monohydrate<\/strong> \u2014 the only form with the full evidence base; HCl\/ethyl-ester\/\u201cbuffered\u201d variants show no proven advantage and far less safety data. Third-party-tested products (NSF, Informed Choice, USP) avoid contamination, the main real-world risk.<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"myths\">\n Beliefs on trial<\/span>\n <h2>The misconceptions table \u2014 claim, verdict, evidence<\/h2>\n <table class=\"wrapok\">\n <caption>Popular beliefs versus the 2015\u20132026 record<\/caption>\n <thead><tr><th>Popular belief<\/th><th>Verdict<\/th><th>What the evidence actually shows<\/th><th>Grade<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>\u201cCreatine destroys your kidneys\u201d<\/td><td class=\"bad\">Debunked in healthy users<\/td><td>Creatinine-based eGFR falls as an artifact; tracer-measured GFR (Cr-EDTA) unchanged across 26 RCTs; urea, albuminuria, proteinuria silent. Untested: pre-existing CKD long-term.<\/td><td>META\u00d74<\/span><\/td><\/tr>\n <tr><td>\u201cIt dehydrates you and causes cramps\u201d<\/td><td class=\"bad\">Debunked \u2014 direction reversed<\/td><td>No hydration\/thermoregulation impairment in controlled studies; heat trials show lower core temperature and better fluid retention; cramping reduced in athlete cohorts.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cCreatine is basically a steroid\u201d<\/td><td class=\"bad\">Debunked<\/td><td>Chemically an amino-acid derivative; no androgen-receptor activity; legal in all major sport; works via phosphagen energetics, not hormones.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cIt makes your hair fall out\u201d<\/td><td class=\"bad\">Debunked (one caveat)<\/td><td>One unreplicated 2009 n=20 DHT study vs 12 null hormone studies and a 2025 direct hair-follicle RCT showing no differences in DHT, DHT:T, or hair growth.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cYou must load 20 g\/day to start\u201d<\/td><td class=\"bad\">Debunked<\/td><td>3\u20135 g\/day reaches identical saturation in 3\u20134 weeks; loading only changes speed and raises GI complaints.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cWomen will get bulky\u201d<\/td><td class=\"bad\">Debunked<\/td><td>Hormonal milieu limits hypertrophy; UNSW sex data show women\u2019s early gain was fluid; long-term changes track training, not supplement.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201c5 g\/day adds extra muscle on top of training\u201d<\/td><td class=\"mid\">Overstated<\/td><td>UNSW wash-in RCT: ~2 kg training gain in both arms, p=0.71. Pooled +1.39 kg FFM across 61 trials is real but water-confounded. Strength\/power benefit stands.<\/td><td>META<\/span><\/td><\/tr>\n <tr><td>\u201cIt damages the liver\u201d<\/td><td class=\"bad\">No signal<\/td><td>Hepatic-marker meta-analyses null; 52-week and adolescent-season data within reference ranges. Existing liver disease: untested, supervise.<\/td><td>META<\/span><\/td><\/tr>\n <tr><td>\u201cGreat for skin \/ anti-aging\u201d<\/td><td class=\"mid\">Commercial, unproven orally<\/td><td>All clinical results are topical, multi-ingredient, Beiersdorf-run, unreplicated. No oral-dose skin evidence.<\/td><td>COM<\/span><\/td><\/tr>\n <tr><td>\u201cEveryone is deficient; it\u2019s a vitamin now\u201d<\/td><td class=\"mid\">Overreach<\/td><td>Insufficiency framing rests on NHANES recall data and one researcher\u2019s proposed DRIs (Tier 4). Real exposed groups: vegans, low-meat elders.<\/td><td>COHORT<\/span><\/td><\/tr>\n <tr><td>\u201cBoosts everyone\u2019s brain\u201d<\/td><td class=\"mid\">Condition-dependent<\/td><td>Small memory\/speed effects concentrated in sleep deprivation, vegetarians, older adults; near-zero in rested young omnivores; no global cognition effect.<\/td><td>META<\/span><\/td><\/tr>\n <tr><td>\u201cMore is better \/ megadosing is dangerous\u201d<\/td><td class=\"mid\">Both wrong<\/td><td>Above saturation, excess is excreted; 685-trial record shows placebo-level side effects at ~12.5 g\/day average; GI upset is the real dose ceiling; >10 g\/day for years unsupervised remains unstudied.<\/td><td>META<\/span><\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"precursors\">\n Adjacent amino acids<\/span>\n <h2>The precursor system and the co-supplement neighbours<\/h2>\n Glycine, arginine and methionine<\/strong> are the three amino acids the body spends to make creatine, and NHANES III (n=29,945) shows precursor availability declines with age \u2014 lowest in adults \u226565, precisely the group with the lowest meat intake and the most muscle to lose. Supplemental creatine measurably spares<\/em> this pathway: it down-regulates AGAT, freeing arginine and glycine for other roles and relieving the ~40% SAMe methylation burden \u2014 a mechanistic argument for supplementation in low-protein contexts that is stronger than most marketing claims, though still Tier 3.<\/p>\n The commonly bundled neighbours, briefly and honestly: guanidinoacetate (GAA)<\/strong> \u2014 creatine\u2019s direct precursor, effective at raising creatine in animal feed science, but raises homocysteine and is not an approved human supplement. \u03b2-alanine<\/strong> \u2014 a genuinely evidence-backed buffer (carnosine) for 1\u20134-minute efforts; a 2025 systematic review of 7 RCTs (n=263) found creatine + \u03b2-alanine co-supplementation adds little beyond each alone, with inconsistent synergy. Taurine and carnitine<\/strong> \u2014 fellow \u201ccarninutrients\u201d absent from plants; neither substitutes for creatine\u2019s phosphagen role. The pattern across all of them: the omnivorous diet quietly supplies a package of nitrogen compounds that vegan diets must synthesise or supplement, and creatine is simply the best-studied member.<\/p>\n<\/section>\n\n<section id=\"tiers\">\n Summary<\/span>\n <h2>Final tier placements<\/h2>\n <table class=\"wrapok\">\n <caption>Every major claim, placed<\/caption>\n <thead><tr><th>Tier<\/th><th>Claims placed here<\/th><\/tr><\/thead>\n <tbody>\n <tr><td class=\"tnum\" style=\"background:#093644;color:#fff;font-weight:700\">TIER 1 HIGH<\/td><td>Creatinine-rise-without-injury artifact \u00b7 safety of 3\u20135 g\/day in healthy adults (685-trial record) \u00b7 repeated-sprint strength\/power ergogenics \u00b7 no dehydration or cramping causation \u00b7 monohydrate as the reference form.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#14556E;color:#fff;font-weight:700\">TIER 2 MODERATE<\/td><td>Pooled lean-mass gain ~1.0\u20131.4 kg (water-confounded; UNSW dissent noted) \u00b7 cognition under metabolic stress (sleep loss, vegetarians, elders) \u00b7 women\u2019s strength gains with resistance training \u00b7 post-menopausal muscle at high dose with training.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#3F6B7E;color:#fff;font-weight:700\">TIER 3 EMERGING<\/td><td>Menopause bone\/sleep signals \u00b7 depression augmentation (esp. women) \u00b7 single-dose brain rescue \u00b7 dietary-insufficiency epidemiology \u00b7 precursor-sparing rationale in low-protein diets \u00b7 fertility energetics.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#96600B;color:#fff;font-weight:700\">TIER 4 CONTESTED<\/td><td>Proposed DRIs (400\/240 mg AI) \u00b7 extra hypertrophy at 5 g\/day \u00b7 ~10 g\/day hypertrophy hypothesis \u00b7 topical skin claims (commercial) \u00b7 use in pre-existing CKD or liver disease \u00b7 perimenopause protocols.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#A63525;color:#fff;font-weight:700\">TIER 5 DEBUNKED<\/td><td>Kidney destruction in healthy users \u00b7 dehydration\/cramping \u00b7 steroid equivalence \u00b7 hair loss \u00b7 mandatory loading \u00b7 \u201cwomen get bulky\u201d \u00b7 fat-gain claims.<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"plain-summary\">\n The questions, answered plainly<\/span>\n <h2>Summary: the popular beliefs versus this evidence base<\/h2>\n\n <h3>Does long-term intake damage the kidneys?<\/h3>\n Not in healthy kidneys, on every creatinine-independent measurement ever taken. Five years of observational use (Poortmans), two years of continuous placebo-controlled use (Bender), tracer-measured GFR trials including on high-protein diets, in diabetics, and in postmenopausal women \u2014 all clean. What long-term intake does do is permanently raise serum creatinine while you take it, which can be misread<\/em> as kidney damage in routine blood work; the harm there is misdiagnosis, not nephrotoxicity. The honest boundary: no long-term RCTs exist in people who already have chronic kidney disease, so pre-existing CKD, a single kidney, or nephrotoxic medication use means physician supervision, not self-experimentation. The popular belief \u201ccreatine destroys kidneys\u201d is debunked for healthy users; the marketing belief \u201cproven safe for everyone forever\u201d overreaches into the untested CKD gap.<\/p>\n\n <h3>Is it good for women\u2019s health?<\/h3>\n Selectively \u2014 and less broadly than the current wave of marketing implies. Best-supported: strength and performance gains alongside resistance training, and the mood\/brain-energetics signal, where the independent Lyoo RCT (52 women, creatine + SSRI) showed one of the largest augmentation effects in the file and imaging trials show the mechanism engaging. Genuinely disappointing: bone \u2014 the two independent 2-year RCTs totalling 437 postmenopausal women found no bone-mineral-density benefit, and the S\u00e3o Paulo trial found no lean-mass or function benefit without training either. Genuinely unknown: perimenopause (first tiny trials only appeared in 2025) and pregnancy (human research reached pharmacokinetics in 2025; all efficacy claims are still animal-model extrapolation \u2014 do not supplement in pregnancy outside a trial). Female physiology (70\u201380% lower stores) makes women plausible high-responders, and female-specific safety data are clean (951 women, no serious adverse events), but \u201cevery woman should take creatine\u201d is a slogan, not a finding.<\/p>\n\n <h3>What are the side effects \u2014 men and women, short and long term?<\/h3>\n Across 685 trials and ~26,000 participants, side-effect rates are statistically indistinguishable from placebo (13.7% vs 13.2% of studies; 4.60% vs 4.21% of participants). The reproducible effects: 1\u20132 kg of intracellular water weight in the first weeks (larger and quicker in women per the UNSW wash-in data \u2014 fluid, not fat or muscle), and dose-dependent GI upset when large boluses (\u226510\u201320 g at once) are taken, solved by splitting doses. Sex-specific fears tested and failed: hair loss\/DHT in men (one unreplicated n=20 study vs a direct 2025 follicle RCT showing nothing), \u201cbulkiness\u201d in women (hormonal ceiling plus fluid misread). Long-term (to 2\u20135 years at 3\u201310 g\/day): no organ-damage signal in kidney, liver, blood, or cardiometabolic panels; the permanent lab artifact on creatinine is the only lasting change. The genuine long-term unknown is unsupervised decades-scale megadosing, which no one has studied.<\/p>\n\n <h3>Will taking it with other nutrients or supplements be damaging or unhealthy?<\/h3>\n No documented harmful nutrient interaction exists. Carbohydrate and protein co-ingestion help<\/em> (insulin-mediated uptake); the high-protein-plus-creatine kidney scare failed its direct tracer-GFR test; \u03b2-alanine coexists neutrally; micronutrients show no adverse interplay. The only substantive debate is caffeine \u2014 a possible blunting of creatine\u2019s performance<\/em> effect under chronic high-dose co-ingestion, unresolved since 1996 and irrelevant to health; normal coffee drinking is fine. The one real-world hazard is not an interaction: it is unverified multi-ingredient products, where most adverse-event reports originate. Plain, third-party-tested creatine monohydrate avoids it.<\/p>\n\n <h3>How much water should be taken with it?<\/h3>\n Normal, thirst-guided intake. The dehydration\/cramping belief is not just unsupported \u2014 controlled studies point the other way (better fluid retention, lower core temperature in heat, fewer cramps in athlete cohorts). Dissolve doses in roughly a glass (250\u2013500 mL) to protect the gut, expect the scale to rise 1\u20132 kg from water stored inside<\/em> muscle cells, and ignore the gallon rule.<\/p>\n\n <div class=\"callout\">\n Boundaries of this summary<\/span>\n These answers apply to healthy adults using plain creatine monohydrate at 3\u201310 g\/day. They do not extend to: pregnancy or breastfeeding (PK data only), anyone under 18 (limited data), pre-existing kidney or liver disease (untested long term), or unverified multi-ingredient products. All figures require verification against primary sources before clinical or published use.<\/p>\n <\/div>\n<\/section>\n\n\n<section id=\"study-table\">\n Study metadata<\/span>\n <h2>The reference base at a glance \u2014 all 73 sources, tabulated<\/h2>\n \n How to read this table: \"\u2014\" = not stated in the citation or in the document text \u00b7 \"n\/a\" = not applicable\n (reviews, meta-analyses, consensus documents and dataset analyses have no single intervention period) \u00b7\n a \"~\" before a country = inferred from the lead author's affiliation, not stated in the source \u00b7\n author counts reflect names listed in the citation, and \"+\" means \"et al.\" (more authors than listed) \u00b7\n calendar dates of trial conduct are almost never stated in citations, so the from\u2013to column is filled only where a source states it.\n Consistent with the standing caveat, every field requires verification against the primary source before clinical or published use.<\/p>\n <table class=\"wrapok\">\n <caption>Study-metadata table \u2014 one row per reference, in reference-list order<\/caption>\n <thead><tr><th>Reference<\/th><th>Research period (duration)<\/th><th>Participants (n)<\/th><th>Researchers (authors listed)<\/th><th>Year published<\/th><th>Study years (from\u2013to)<\/th><th>Country<\/th><th>Type<\/th><th>Section<\/th><\/tr><\/thead>\n <tbody>\n<tr><td class=\"tnum\">Brosnan 2016<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>2<\/td><td>2016<\/td><td>\u2014<\/td><td>~Canada<\/td><td>INDEPENDENT<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2026 (DRI proposal)<\/strong><\/td><td>n\/a (DRI proposal)<\/td><td>\u2014<\/td><td>1<\/td><td>2026<\/td><td>\u2014<\/td><td>~Norway<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Nedeljkovic 2025<\/strong><\/td><td>n\/a (dietary-exposure analysis)<\/td><td>\u2014<\/td><td>2<\/td><td>2025<\/td><td>\u2014<\/td><td>~Norway\/Serbia<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2021<\/strong><\/td><td>n\/a (dietary survey)<\/td><td>4,291 (children)<\/td><td>1<\/td><td>2021<\/td><td>\u2014<\/td><td>~Serbia<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2026 (NHANES mortality)<\/strong><\/td><td>n\/a (linked-mortality cohort)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2026<\/td><td>NHANES (years not stated)<\/td><td>USA (data)<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Candow 2025<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~Canada<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Desai 2025 (UNSW)<\/strong><\/td><td>7 d wash-in + 12 wk training<\/td><td>63<\/td><td>7<\/td><td>2025<\/td><td>\u2014<\/td><td>Australia<\/td><td>INDEPENDENT \u2014 design\/lead<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Barranco-Gil 2024<\/strong><\/td><td>6 d loading (20 g\/d)<\/td><td>23<\/td><td>1+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>Spain<\/td><td>INDEPENDENT<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Ashtary-Larky 2025 (61 trials)<\/strong><\/td><td>n\/a (meta-analysis, 61 trials)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~multinational<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Burke 2023<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2023<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Backx 2017<\/strong><\/td><td>leg-immobilization RCT<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2017<\/td><td>\u2014<\/td><td>~Netherlands<\/td><td>INDEPENDENT<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Int Urol Nephrol 2026<\/strong><\/td><td>n\/a (meta-analysis, 26 RCTs)<\/td><td>1,036<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">KabiriNaeini 2025<\/strong><\/td><td>n\/a (meta-analysis, 21 studies)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~Iran<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Tsiaras 2026<\/strong><\/td><td>n\/a (meta-analysis, 19 RCTs)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">de Souza e Silva 2019<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2019<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Renal Failure 2024 (MR)<\/strong><\/td><td>n\/a (Mendelian randomization)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2024<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Gualano 2011<\/strong><\/td><td>12 wk<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2011<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Poortmans & Francaux 1999<\/strong><\/td><td>10 mo\u20135 yr of use<\/td><td>\u2014<\/td><td>2<\/td><td>1999<\/td><td>\u2014<\/td><td>~Belgium<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Kreider 2003<\/strong><\/td><td>21 mo<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2003<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Gualano 2008<\/strong><\/td><td>12 wk<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2008<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Lugaresi 2013<\/strong><\/td><td>12 wk<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2013<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Neves 2011<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2011<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Bender 2008<\/strong><\/td><td>2 yr<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2008<\/td><td>\u2014<\/td><td>~Germany<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Gualano 2010<\/strong><\/td><td>short-term, high dose<\/td><td>1 (single kidney)<\/td><td>3+ (et al.)<\/td><td>2010<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Longobardi 2023<\/strong><\/td><td>n\/a (narrative review)<\/td><td>\u2014<\/td><td>4<\/td><td>2023<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Pritchard & Kalra 1998<\/strong><\/td><td>n\/a (case letter)<\/td><td>1<\/td><td>2<\/td><td>1998<\/td><td>\u2014<\/td><td>~UK<\/td><td>INDEPENDENT \u2014 n=1, pre-existing kidney disease<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Kreider 2025 (685 trials)<\/strong><\/td><td>n\/a (685-trial dataset)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Sports 2026 (684 RCTs)<\/strong><\/td><td>n\/a (dose\u2013response, 684 RCTs)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Longobardi 2025<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>4<\/td><td>2025<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT \u2014 academic; some cluster overlap<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Alizadeh 2022<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2022<\/td><td>\u2014<\/td><td>~Iran<\/td><td>INDEPENDENT<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Kashi 2024<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Cureus 2026 (adolescents)<\/strong><\/td><td>n\/a (systematic review)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Kreider 2017 (position stand)<\/strong><\/td><td>n\/a (consensus)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2017<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Gordji-Nejad 2024<\/strong><\/td><td>single dose \u00b7 21 h sleep deprivation<\/td><td>15<\/td><td>2+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>Germany (J\u00fclich)<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Nutrients 2026 (0.2 g\/kg)<\/strong><\/td><td>single dose<\/td><td>29<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Xu 2024<\/strong><\/td><td>n\/a (meta-analysis, 16 RCTs)<\/td><td>492<\/td><td>4<\/td><td>2024<\/td><td>\u2014<\/td><td>~China<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Rae 2003<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2003<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Smith-Ryan 2025<\/strong><\/td><td>n\/a (lifespan review)<\/td><td>\u2014<\/td><td>6<\/td><td>2025<\/td><td>\u2014<\/td><td>~USA\/Australia<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Smith-Ryan 2021<\/strong><\/td><td>n\/a (lifespan review)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2021<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">de Guingand 2020<\/strong><\/td><td>n\/a (meta-analysis, 29 studies)<\/td><td>951<\/td><td>5<\/td><td>2020<\/td><td>\u2014<\/td><td>Australia (Monash)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Gordon 2023<\/strong><\/td><td>loading, both cycle phases (crossover)<\/td><td>39<\/td><td>1+ (et al.)<\/td><td>2023<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Hall 2025<\/strong><\/td><td>quasi-experimental<\/td><td>15<\/td><td>4<\/td><td>2025<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">CONCRET-MENOPA 2025<\/strong><\/td><td>8 wk<\/td><td>36<\/td><td>not listed<\/td><td>2025<\/td><td>\u2014<\/td><td>\u2014<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2024 (NHANES)<\/strong><\/td><td>n\/a (NHANES survey)<\/td><td>\u2014<\/td><td>4<\/td><td>2024<\/td><td>2017\u20132020 (NHANES)<\/td><td>USA (data)<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Ellery 2016<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>3<\/td><td>2016<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Chilibeck 2015<\/strong><\/td><td>12 mo<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2015<\/td><td>\u2014<\/td><td>~Canada<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Chilibeck 2023<\/strong><\/td><td>2 yr<\/td><td>237<\/td><td>3+ (et al.)<\/td><td>2023<\/td><td>\u2014<\/td><td>Canada (Saskatchewan\/Regina)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Sales 2020<\/strong><\/td><td>2 yr<\/td><td>200 (osteopenia)<\/td><td>2+ (et al.)<\/td><td>2020<\/td><td>\u2014<\/td><td>Brazil (S\u00e3o Paulo)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Postmenopausal meta 2025<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2025<\/td><td>searches to Aug 2025<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Lyoo 2012<\/strong><\/td><td>8 wk<\/td><td>52<\/td><td>3+ (et al.)<\/td><td>2012<\/td><td>\u2014<\/td><td>~South Korea<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Yoon 2016<\/strong><\/td><td>8 wk<\/td><td>34 (imaging arm)<\/td><td>2+ (et al.)<\/td><td>2016<\/td><td>\u2014<\/td><td>~South Korea<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Kondo 2016<\/strong><\/td><td>8 wk, dose-ranging 2\/4\/10 g\/d<\/td><td>33<\/td><td>2+ (et al.)<\/td><td>2016<\/td><td>\u2014<\/td><td>USA (NIMH-funded)<\/td><td>INDEPENDENT \u2014 NIMH<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Fares 2026<\/strong><\/td><td>n\/a (systematic review)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2026<\/td><td>\u2014<\/td><td>~Canada<\/td><td>INDEPENDENT \u2014 cluster co-authors noted<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Dickinson 2016<\/strong><\/td><td>n\/a (retrospective cohort)<\/td><td>287<\/td><td>3+ (et al.)<\/td><td>2016<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">de Guingand 2024 (CPO)<\/strong><\/td><td>pregnancy (prospective cohort)<\/td><td>282<\/td><td>6<\/td><td>2024<\/td><td>\u2014<\/td><td>Australia (Hudson\/Monash)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Muccini 2021<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2021<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Naidu 2025<\/strong><\/td><td>dose-escalation PK (pregnancy)<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>Australia (Monash)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Freeman 2025<\/strong><\/td><td>full-term pregnancy (animal model)<\/td><td>n\/a (guinea pigs)<\/td><td>4<\/td><td>2025<\/td><td>\u2014<\/td><td>~Australia\/NZ<\/td><td>INDEPENDENT \u2014 preclinical<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Lak 2025<\/strong><\/td><td>12 wk<\/td><td>45<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~Iran + intl.<\/td><td>ISSN-CLUSTER \u2014 only direct hair evidence; concordant with 12 independent hormone datasets<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">van der Merwe 2009<\/strong><\/td><td>3 wk<\/td><td>20<\/td><td>3<\/td><td>2009<\/td><td>\u2014<\/td><td>~South Africa<\/td><td>INDEPENDENT \u2014 single unreplicated origin of the myth<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">Antonio 2021<\/strong><\/td><td>n\/a (consensus)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2021<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER \u2014 consensus document<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">Antonio 2024 (Part II)<\/strong><\/td><td>n\/a (consensus)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER \u2014 consensus document<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">Peirano 2011<\/strong><\/td><td>6 wk<\/td><td>43 (men)<\/td><td>2+ (et al.)<\/td><td>2011<\/td><td>\u2014<\/td><td>Germany<\/td><td>COMMERCIAL \u2014 Beiersdorf<\/span><\/td><td>Skin<\/td><\/tr>\n<tr><td class=\"tnum\">Lenz 2005<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2005<\/td><td>\u2014<\/td><td>Germany<\/td><td>COMMERCIAL \u2014 Beiersdorf<\/span><\/td><td>Skin<\/td><\/tr>\n<tr><td class=\"tnum\">Knott 2008<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2008<\/td><td>\u2014<\/td><td>Germany<\/td><td>COMMERCIAL \u2014 Beiersdorf<\/span><\/td><td>Skin<\/td><\/tr>\n<tr><td class=\"tnum\">Elosegui 2022<\/strong><\/td><td>n\/a (systematic review, 10 studies)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2022<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Trexler & Smith-Ryan 2015<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>2<\/td><td>2015<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Vandenberghe 1996<\/strong><\/td><td>loading period<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>1996<\/td><td>\u2014<\/td><td>~Belgium<\/td><td>INDEPENDENT \u2014 origin of the caffeine debate, contested since<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Green 1996<\/strong><\/td><td>acute\/loading<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>1996<\/td><td>\u2014<\/td><td>~UK<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Steenge 2000<\/strong><\/td><td>acute<\/td><td>\u2014<\/td><td>3<\/td><td>2000<\/td><td>\u2014<\/td><td>~UK<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Sci Rep 2026 (4-group RCT)<\/strong><\/td><td>\u2014<\/td><td>60<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Stecker 2019<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>5<\/td><td>2019<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Ashtary-Larky 2025 (\u03b2-alanine)<\/strong><\/td><td>n\/a (systematic review, 7 RCTs)<\/td><td>263<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~multinational<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Adjacent co-supplements<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"references\" class=\"refs\">\n Sources<\/span>\n <h2>References \u2014 grouped, with independence tags<\/h2>\n INDEPENDENT<\/span> no disclosed supplement-industry ties ISSN-CLUSTER<\/span> rigorous but industry-adjacent authorship\/venue COMMERCIAL<\/span> manufacturer-run<\/p>\n\n <h3>Requirement, synthesis & precursor amino acids<\/h3>\n <ol>\n <li>Brosnan JT, Brosnan ME. The role of dietary creatine. Amino Acids<\/i> 2016;48:1785\u20131791. doi:10.1007\/s00726-016-2188-1<\/span> INDEPENDENT<\/span><\/li>\n <li>Ostojic SM. Establishing Dietary Reference Intakes for creatine in adults. Nutrition Reviews<\/i> 2026;nuag009. doi:10.1093\/nutrit\/nuag009<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Nedeljkovic D, Ostojic SM. Dietary exposure to creatine-precursor amino acids in the general population. Amino Acids<\/i> 2025;57:29. doi:10.1007\/s00726-025-03460-7<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ostojic SM. Creatine as a food supplement for the general population. J Functional Foods<\/i> 2021;83:104568. doi:10.1016\/j.jff.2021.104568<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ostojic SM et al. Dietary creatine intake and all-cause mortality: NHANES linked-mortality analysis. Appl Physiol Nutr Metab<\/i> 2026. doi:10.1139\/apnm-2025-0001<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Candow DG, Ostojic SM, Chilibeck PD, et al. Creatine monohydrate supplementation for older adults and clinical populations. JISSN<\/i> 2025;22(sup1):2534130. doi:10.1080\/15502783.2025.2534130<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n\n <h3>Muscle & strength \u2014 including dissenting independents<\/h3>\n <ol>\n <li>Desai I, Pandit A, Smith-Ryan AE, Simar D, Candow DG, Kaakoush NO, Hagstrom AD. The effect of creatine supplementation on lean body mass with and without resistance training. Nutrients<\/i> 2025;17(6):1081. doi:10.3390\/nu17061081<\/span> INDEPENDENT (design\/lead)<\/span><\/li>\n <li>Barranco-Gil D, et al. High-dose short-term creatine supplementation without beneficial effects in professional cyclists: RCT. JISSN<\/i> 2024;21:2340574. doi:10.1080\/15502783.2024.2340574<\/span> INDEPENDENT<\/span><\/li>\n <li>Ashtary-Larky D, et al. Creatine supplementation and resistance training: novice vs experienced lifters \u2014 systematic review and dose\u2013response meta-analysis (61 trials). JISSN<\/i> 2025;22(sup1):2586523. doi:10.1080\/15502783.2025.2586523<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Burke R, Pi\u00f1ero A, Coleman M, et al. Creatine + resistance training and regional hypertrophy: systematic review with meta-analysis. Nutrients<\/i> 2023;15(9):2116. doi:10.3390\/nu15092116<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Backx EMP, et al. Creatine loading does not preserve muscle mass or strength during leg immobilization: RCT. Sports Med<\/i> 2017;47:1661\u20131671. doi:10.1007\/s40279-016-0670-2<\/span> INDEPENDENT<\/span><\/li>\n <\/ol>\n\n <h3>Kidney<\/h3>\n <ol>\n <li>[Anon. authors] Impact of creatine supplementation on kidney health: systematic review and meta-analysis (26 RCTs, Cr-EDTA subanalysis). Int Urol Nephrol<\/i> 2026. doi:10.1007\/s11255-026-05287-x<\/span> INDEPENDENT<\/span><\/li>\n <li>KabiriNaeini E, Eskandari M, Mortazavi M, et al. Effect of creatine supplementation on kidney function: systematic review and meta-analysis. BMC Nephrology<\/i> 2025;26:622. doi:10.1186\/s12882-025-04558-6<\/span> INDEPENDENT<\/span><\/li>\n <li>Tsiaras A, et al. The effect of creatine supplementation on kidney function: systematic review and meta-analysis of RCTs. J Renal Nutrition<\/i> 2026. doi:10.1016\/S1051-2276(26)00082-8<\/span> INDEPENDENT<\/span><\/li>\n <li>de Souza e Silva A, et al. Effects of creatine supplementation on renal function: systematic review and meta-analysis. J Renal Nutrition<\/i> 2019;29(6):480\u2013489. doi:10.1053\/j.jrn.2019.05.004<\/span> INDEPENDENT<\/span><\/li>\n <li>Exploring creatine supplementation and renal function: Mendelian randomization analysis. Renal Failure<\/i> 2024;46(2):2364762. doi:10.1080\/0886022X.2024.2364762<\/span> INDEPENDENT<\/span><\/li>\n <li>Gualano B, et al. Creatine supplementation does not impair kidney function in type 2 diabetic patients: RCT (\u2075\u00b9Cr-EDTA). Eur J Appl Physiol<\/i> 2011;111:749\u2013756. doi:10.1007\/s00421-010-1676-3<\/span> INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/li>\n <li>Poortmans JR, Francaux M. Long-term oral creatine supplementation does not impair renal function in healthy athletes (10 mo\u20135 yr). Med Sci Sports Exerc<\/i> 1999;31:1108\u20131110. doi:10.1097\/00005768-199908000-00005<\/span> INDEPENDENT<\/span><\/li>\n <li>Kreider RB, et al. Long-term creatine supplementation does not significantly affect clinical markers of health in athletes (21 mo). Mol Cell Biochem<\/i> 2003;244:95\u2013104. doi:10.1023\/A:1022469320296<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Gualano B, Ugrinowitsch C, et al. Effects of creatine supplementation on renal function: RCT with cystatin C. Eur J Appl Physiol<\/i> 2008;103:33\u201340. doi:10.1007\/s00421-007-0669-3<\/span> INDEPENDENT<\/span><\/li>\n <li>Lugaresi R, Leme M, de Salles Painelli V, et al. Does long-term creatine supplementation impair kidney function in resistance-trained individuals consuming a high-protein diet? (\u2075\u00b9Cr-EDTA). JISSN<\/i> 2013;10:26. doi:10.1186\/1550-2783-10-26<\/span> INDEPENDENT<\/span><\/li>\n <li>Neves M Jr, Gualano B, et al. Effect of creatine supplementation on measured glomerular filtration rate in postmenopausal women. Appl Physiol Nutr Metab<\/i> 2011;36:419\u2013422. doi:10.1139\/h11-014<\/span> INDEPENDENT<\/span><\/li>\n <li>Bender A, et al. Long-term creatine supplementation is safe in aged patients with Parkinson disease (2-yr, renal markers incl. cystatin C). Nutr Res<\/i> 2008;28:172\u2013178. doi:10.1016\/j.nutres.2008.01.001<\/span> INDEPENDENT<\/span><\/li>\n <li>Gualano B, Ferreira DC, Sapienza MT, et al. Effect of short-term high-dose creatine supplementation on measured GFR in a young man with a single kidney. Am J Kidney Dis<\/i> 2010;55(3):e7\u2013e9. doi:10.1053\/j.ajkd.2009.10.053<\/span> INDEPENDENT<\/span><\/li>\n <li>Longobardi I, Gualano B, Seguro AC, Roschel H. Is it time for a requiem for creatine supplementation-induced kidney failure? A narrative review. Nutrients<\/i> 2023;15:1466. doi:10.3390\/nu15061466<\/span> INDEPENDENT<\/span><\/li>\n <li>Pritchard NR, Kalra PA. Renal dysfunction accompanying oral creatine supplements (case letter \u2014 provenance of the scare). Lancet<\/i> 1998;351:1252\u20131253. doi:10.1016\/S0140-6736(05)79319-3<\/span> INDEPENDENT \u2014 n=1, pre-existing kidney disease<\/span><\/li>\n <\/ol>\n\n <h3>Safety, liver & adverse events<\/h3>\n <ol>\n <li>Kreider RB, et al. Safety of creatine supplementation: prevalence of reported side effects in clinical trials and adverse event reports (685 trials). JISSN<\/i> 2025;22:2488937. doi:10.1080\/15502783.2025.2488937<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Creatine supplementation dose and duration are not associated with increased side effects: study-level dose\u2013response analysis of 684 RCTs. Sports<\/i> 2026;14(4):137. doi:10.3390\/sports14040137<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Longobardi I, Solis MY, Roschel H, Gualano B. A short review of the most common safety concerns regarding creatine ingestion. Frontiers in Nutrition<\/i> 2025;12:1682746. doi:10.3389\/fnut.2025.1682746<\/span> INDEPENDENT (academic; some cluster overlap)<\/span><\/li>\n <li>Alizadeh S, et al. Effects of creatine supplementation on hepatic markers: systematic review and meta-analysis. Sports Med Open<\/i> 2022;8:126. doi:10.1186\/s40798-022-00518-w<\/span> INDEPENDENT<\/span><\/li>\n <li>Kashi S, et al. Effects of creatine supplementation on renal and hepatic function: systematic review and meta-analysis. Nutr Res Rev<\/i> 2024;37:E30. doi:10.1017\/S095442242400003X<\/span> INDEPENDENT<\/span><\/li>\n <li>Evaluating the safety of creatine monohydrate in adolescents: systematic review of renal, hepatic and cardiometabolic outcomes. Cureus<\/i> 2026. INDEPENDENT<\/span><\/li>\n <li>Kreider RB, et al. ISSN position stand: safety and efficacy of creatine supplementation. JISSN<\/i> 2017;14:18. doi:10.1186\/s12970-017-0173-z<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n\n <h3>Brain, cognition & mood<\/h3>\n <ol>\n <li>Gordji-Nejad A, Matusch A, et al. Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation. Scientific Reports<\/i> 2024;14:4937. doi:10.1038\/s41598-024-54249-9<\/span> INDEPENDENT<\/span><\/li>\n <li>Single-dose creatine (0.2 g\/kg) reduces sleep-deprivation-induced deterioration in cognitive performance. Nutrients<\/i> 2026;18(8):1192. doi:10.3390\/nu18081192<\/span> INDEPENDENT<\/span><\/li>\n <li>Xu C, Bi S, Zhang W, Luo L. Effects of creatine supplementation on cognitive function in adults: systematic review and meta-analysis (16 RCTs). Frontiers in Nutrition<\/i> 2024;11:1424972. doi:10.3389\/fnut.2024.1424972<\/span> INDEPENDENT<\/span><\/li>\n <li>Rae C, et al. Oral creatine monohydrate supplementation improves brain performance (vegetarians). Proc Biol Sci<\/i> 2003;270:2147\u20132150. doi:10.1098\/rspb.2003.2492<\/span> INDEPENDENT<\/span><\/li>\n <\/ol>\n\n <h3>Women\u2019s health<\/h3>\n <ol>\n <li>Smith-Ryan AE, DelBiondo GM, Brown AF, Kleiner SM, Tran NT, Ellery SJ. Creatine in women\u2019s health: bridging the gap from menstruation through pregnancy to menopause. JISSN<\/i> 2025;22:2502094. doi:10.1080\/15502783.2025.2502094<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Smith-Ryan AE, et al. Creatine supplementation in women\u2019s health: a lifespan perspective. Nutrients<\/i> 2021;13(3):877. doi:10.3390\/nu13030877<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>de Guingand DL, Palmer KR, Snow RJ, Davies-Tuck ML, Ellery SJ. Risk of adverse outcomes in females taking oral creatine monohydrate: systematic review and meta-analysis. Nutrients<\/i> 2020;12(6):1780. doi:10.3390\/nu12061780<\/span> INDEPENDENT<\/span><\/li>\n <li>Gordon AN, et al. Creatine monohydrate loading and exercise recovery in active women throughout the menstrual cycle. Nutrients<\/i> 2023;15(16):3567. doi:10.3390\/nu15163567<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Hall L, Klassen S, Holbein J, Waters J. Impact of creatine supplementation on menopausal women\u2019s body composition, cognition, estrogen, strength, and sleep. JISSN<\/i> 2025;22:2533673. doi:10.1080\/15502783.2025.2533673<\/span> INDEPENDENT<\/span><\/li>\n <li>CONCRET-MENOPA: 8-week creatine HCl \/ ethyl ester RCT in perimenopausal and menopausal women. J Am Nutr Assoc<\/i> 2025;45(3):199\u2013210. doi:10.1080\/27697061.2025.2551184<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ostojic SM, Stea TH, Ellery SJ, Smith-Ryan AE. Dietary creatine intake and female reproductive health: NHANES 2017\u20132020. Food Sci Nutr<\/i> 2024;12:4135. doi:10.1002\/fsn3.4135<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ellery SJ, Walker DW, Dickinson H. Creatine for women: creatine and the reproductive cycle. Amino Acids<\/i> 2016;48:1807\u20131817. doi:10.1007\/s00726-016-2199-y<\/span> INDEPENDENT<\/span><\/li>\n <li>Chilibeck PD, et al. Effects of creatine and resistance training on bone health in postmenopausal women (12-mo RCT). Med Sci Sports Exerc<\/i> 2015;47:1587\u20131595. doi:10.1249\/MSS.0000000000000571<\/span> INDEPENDENT<\/span><\/li>\n <li>Chilibeck PD, Candow DG, Gordon JJ, et al. A 2-yr randomized controlled trial on creatine supplementation during exercise for postmenopausal bone health (n=237). Med Sci Sports Exerc<\/i> 2023;55:1750\u20131760. doi:10.1249\/MSS.0000000000003202<\/span> INDEPENDENT \u2014 Univ. Saskatchewan\/Regina<\/span><\/li>\n <li>Sales LP, Pinto AJ, et al. (Gualano group). Creatine supplementation (3 g\/d) and bone health in older women: a 2-year randomized placebo-controlled trial (n=200, osteopenia). J Gerontol A Biol Sci Med Sci<\/i> 2020;75:931\u2013938. doi:10.1093\/gerona\/glz162<\/span> INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/li>\n <li>Creatine monohydrate for lean mass, strength, and bone density in postmenopausal women: systematic review and meta-analysis (searches to Aug 2025). PubMed<\/i> 42141930. INDEPENDENT<\/span><\/li>\n <li>Lyoo IK, Yoon S, Kim TS, et al. Oral creatine monohydrate augmentation for enhanced response to an SSRI in women with major depressive disorder: randomized double-blind placebo-controlled trial (n=52). Am J Psychiatry<\/i> 2012;169:937\u2013945. doi:10.1176\/appi.ajp.2012.12010009<\/span> INDEPENDENT<\/span><\/li>\n <li>Yoon S, Kim JE, et al. Effects of creatine monohydrate augmentation on brain metabolic and network outcome measures in women with MDD. Biol Psychiatry<\/i> 2016;80:439\u2013447. doi:10.1016\/j.biopsych.2015.11.027<\/span> INDEPENDENT<\/span><\/li>\n <li>Kondo DG, Forrest LN, et al. Creatine target engagement with brain bioenergetics: dose-ranging \u00b3\u00b9P-MRS study of adolescent females with SSRI-resistant depression (2\/4\/10 g\/d). Amino Acids<\/i> 2016;48:1941\u20131954. doi:10.1007\/s00726-016-2194-3<\/span> INDEPENDENT \u2014 NIMH<\/span><\/li>\n <li>Fares BJ, Zhou C, Fabiano N, et al. The effect of creatine monohydrate on mental disorders: systematic review of RCTs. Can J Psychiatry<\/i> 2026. doi:10.1177\/07067437251408171<\/span> INDEPENDENT (cluster co-authors noted)<\/span><\/li>\n <li>Dickinson H, Davies-Tuck M, Ellery SJ, et al. Maternal creatine in pregnancy: a retrospective cohort study (n=287). BJOG<\/i> 2016;123:1830\u20131838. doi:10.1111\/1471-0528.14237<\/span> INDEPENDENT<\/span><\/li>\n <li>de Guingand DL, Palmer KR, Callahan DL, Snow RJ, Davies-Tuck ML, Ellery SJ. Creatine and pregnancy outcomes (CPO): prospective cohort study of creatine metabolism in low-risk pregnant females (n=282). Am J Clin Nutr<\/i> 2024;119:838\u2013849. doi:10.1016\/j.ajcnut.2023.11.006<\/span> INDEPENDENT \u2014 Hudson Institute\/Monash<\/span><\/li>\n <li>Muccini AM, Tran NT, de Guingand DL, et al. Creatine metabolism in female reproduction, pregnancy and newborn health. Nutrients<\/i> 2021;13:490. doi:10.3390\/nu13020490<\/span> INDEPENDENT<\/span><\/li>\n <li>Naidu M, de Guingand DL, et al. Open label, dose escalation trial of creatine monohydrate in pregnancy (first human supplementation PK data). JISSN<\/i> 2025;22:2533652. doi:10.1080\/15502783.2025.2533652<\/span> INDEPENDENT \u2014 Monash<\/span><\/li>\n <li>Freeman AK, Dyson RM, Berry MJ, Ellery SJ. Safety of maternal creatine supplementation: guinea pig model of full-term pregnancy. JISSN<\/i> 2025;22:2533674. doi:10.1080\/15502783.2025.2533674<\/span> INDEPENDENT \u2014 preclinical<\/span><\/li>\n <\/ol>\n\n <h3>Men\u2019s health, hair & hormones<\/h3>\n <ol>\n <li>Lak M, Forbes SC, Ashtary-Larky D, et al. Does creatine cause hair loss? A 12-week randomized controlled trial. JISSN<\/i> 2025;22:2495229. doi:10.1080\/15502783.2025.2495229<\/span> ISSN-CLUSTER (only direct evidence; concordant with 12 independent hormone datasets)<\/span><\/li>\n <li>van der Merwe J, Brooks NE, Myburgh KH. Three weeks of creatine monohydrate supplementation affects DHT:T ratio in college-aged rugby players. Clin J Sport Med<\/i> 2009;19:399\u2013404. doi:10.1097\/JSM.0b013e3181b8b52f<\/span> INDEPENDENT \u2014 the single unreplicated origin of the myth<\/span><\/li>\n <li>Antonio J, Candow DG, Forbes SC, et al. Common questions and misconceptions about creatine supplementation. JISSN<\/i> 2021;18:13. doi:10.1186\/s12970-021-00412-w<\/span> ISSN-CLUSTER \u2014 consensus document<\/span><\/li>\n <li>Antonio J, et al. Part II: Common questions and misconceptions about creatine supplementation. JISSN<\/i> 2024;21:2441760. doi:10.1080\/15502783.2024.2441760<\/span> ISSN-CLUSTER \u2014 consensus document<\/span><\/li>\n <\/ol>\n\n <h3>Skin \u2014 flagged commercial<\/h3>\n <ol>\n <li>Peirano RI, Achterberg V, et al. Dermal penetration of creatine from a face-care formulation containing creatine, guarana and glycerol: antiwrinkle and antisagging efficacy in male subjects. J Cosmetic Dermatol<\/i> 2011;10:273\u2013281. doi:10.1111\/j.1473-2165.2011.00579.x<\/span> COMMERCIAL \u2014 Beiersdorf<\/span><\/li>\n <li>Lenz H, et al. The creatine kinase system in human skin: protective effects of creatine against oxidative and UV damage. J Invest Dermatol<\/i> 2005;124:443\u2013452. doi:10.1111\/j.0022-202X.2004.23522.x<\/span> COMMERCIAL \u2014 Beiersdorf<\/span><\/li>\n <li>Knott A, Fischer F, et al. Folic acid and creatine improve the firmness of human skin in vivo. J Cosmetic Dermatol<\/i> 2008. COMMERCIAL \u2014 Beiersdorf<\/span><\/li>\n <\/ol>\n\n <h3>Co-ingestion & interactions<\/h3>\n <ol>\n <li>Elosegui S, et al. Interaction between caffeine and creatine when used as concurrent ergogenic supplements: systematic review (10 studies). Int J Sport Nutr Exerc Metab<\/i> 2022;32:285\u2013295. doi:10.1123\/ijsnem.2021-0262<\/span> INDEPENDENT<\/span><\/li>\n <li>Trexler ET, Smith-Ryan AE. Creatine and caffeine: considerations for concurrent supplementation. Int J Sport Nutr Exerc Metab<\/i> 2015;25:607\u2013623. doi:10.1123\/ijsnem.2014-0193<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Vandenberghe K, et al. Caffeine counteracts the ergogenic action of muscle creatine loading. J Appl Physiol<\/i> 1996;80:452\u2013457. doi:10.1152\/jappl.1996.80.2.452<\/span> INDEPENDENT \u2014 origin of the caffeine debate, contested since<\/span><\/li>\n <li>Green AL, Hultman E, Macdonald IA, et al. Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans. Am J Physiol<\/i> 1996;271:E821\u2013E826. doi:10.1152\/ajpendo.1996.271.5.E821<\/span> INDEPENDENT<\/span><\/li>\n <li>Steenge GR, Simpson EJ, Greenhaff PL. Protein- and carbohydrate-induced augmentation of whole body creatine retention in humans. J Appl Physiol<\/i> 2000;89:1165\u20131171. doi:10.1152\/jappl.2000.89.3.1165<\/span> INDEPENDENT<\/span><\/li>\n <li>Synergistic effects of creatine, carbohydrates and protein on repeated sprint performance (4-group RCT, n=60). Scientific Reports<\/i> 2026. doi:10.1038\/s41598-026-44278-x<\/span> INDEPENDENT<\/span><\/li>\n <li>Stecker RA, Harty PS, Jagim AR, Candow DG, Kerksick CM. Timing of ergogenic aids and micronutrients on muscle and exercise performance. JISSN<\/i> 2019;16:37. doi:10.1186\/s12970-019-0304-9<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n\n <h3>Adjacent amino-acid co-supplements<\/h3>\n <ol>\n <li>Ashtary-Larky D, Candow DG, Forbes SC, et al. Effects of creatine and \u03b2-alanine co-supplementation on exercise performance and body composition: systematic review (7 RCTs, n=263). Nutrients<\/i> 2025;17(13):2074. doi:10.3390\/nu17132074<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n<\/section>\n\n<footer>\n SCOPE & DISCLAIMER.<\/strong> Companion dossier to \u201cHuman Nutrient Requirements \u2014 The Certainty Pyramid,\u201d same visual grammar: width = evidentiary weight, colour depth = certainty, solid fills only, five-step ramp #093644 \u2192 #A63525. Compiled from live literature search, August 2026. All effect estimates, confidence intervals and trial figures require independent verification against primary sources before publication or clinical use. This document is a scientific literature review, not individualised medical or nutritional advice; anyone pregnant, under 18, with kidney or liver disease, or taking medication should involve a physician or registered dietitian before beginning supplementation.<\/p>\n<\/footer>\n\n<\/div>\n<\/body>\n<\/html>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"Creatine on the Certainty Pyramid – Requirements, Risks and Myths Rebuilt from Primary Literature (2015\u20132026) EVIDENCE REVIEW \u00b7 SUPPLEMENT DOSSIER N\u00ba 2 \u00b7 COMPANION TO \u201cHUMAN NUTRIENT REQUIREMENTS\u201d Facts About Creatine Requirements, kidneys (including the full long-term record), water, liver, skin, muscle, brain, women\u2019s health (bone, mood, pregnancy, menopause \u2014 trial by trial), men\u2019s health, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"elementor_canvas","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[37,26,28,27,25,39,38],"class_list":["post-821","post","type-post","status-publish","format-standard","hentry","category-text","tag-creatine","tag-food","tag-food-2026","tag-nutrition","tag-nutrition-2026","tag-nutritious-facts","tag-supplement"],"_links":{"self":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts\/821","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/comments?post=821"}],"version-history":[{"count":4,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts\/821\/revisions"}],"predecessor-version":[{"id":826,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts\/821\/revisions\/826"}],"wp:attachment":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/media?parent=821"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/categories?post=821"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/tags?post=821"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

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3.4rem;font-family:var(--mono);font-size:0.78rem;color:var(--ink-soft)}\nfooter p{max-width:90ch}\n\n@media (max-width:640px){\n table{display:block;overflow-x:auto;white-space:nowrap}\n table.wrapok{white-space:normal}\n}\n@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}\n<\/style>\n<\/head>\n<body>\n<div class=\"shell\">\n\n<header class=\"hero\">\n <div class=\"kicker\">EVIDENCE REVIEW \u00b7 SUPPLEMENT DOSSIER N\u00ba 2 \u00b7 COMPANION TO \u201cHUMAN NUTRIENT REQUIREMENTS\u201d<\/div>\n <h1>Facts About Creatine<\/h1>\n Requirements, kidneys (including the full long-term record), water, liver, skin, muscle, brain, women\u2019s health (bone, mood, pregnancy, menopause \u2014 trial by trial), men\u2019s health, co-ingestion with other nutrients and supplements, and overdose \u2014 rebuilt from primary literature, 2015\u20132026, with independent studies weighted above commercial ones and the popular beliefs put on trial.<\/p>\n <div class=\"hero-meta\">\n METHOD primary papers & meta-analyses, live-searched<\/b><\/span>\n WINDOW 2015\u20132026 (anchors to 2009 where provenance demands)<\/b><\/span>\n GRADING five-tier certainty ramp, solid fills<\/b><\/span>\n FUNDING independence flagged per source<\/b><\/span>\n <\/div>\n<\/header>\n\n<section id=\"caveat\">\n <div class=\"callout\">\n Standing verification caveat \u2014 preserved from the parent project<\/span>\n Every effect estimate, confidence interval, sample size and trial figure in this document was drawn from live literature search of the sources listed in the references, but must be independently verified against the primary PDFs<\/strong> before publication, clinical use, or citation in derivative work. Several 2025\u20132026 papers are recent enough that corrections may follow. This is a scientific literature review, not individualised medical advice: anyone pregnant, with kidney or liver disease, under 18, or on medication should involve a physician or registered dietitian before supplementing.<\/p>\n <\/div>\n <div class=\"callout amber\">\n Funding-independence note \u2014 read before the findings<\/span>\n Creatine research has an unusual structure: the most-cited review authors (the ISSN cluster \u2014 Kreider, Antonio, Candow, Forbes, Smith-Ryan, Ostojic and colleagues) are rigorous and prolific, but many disclose funding or advisory ties to creatine manufacturers, and several defining \u201cmisconceptions\u201d reviews appear in the ISSN\u2019s own journal. That does not make them wrong \u2014 most of their claims are independently replicated \u2014 but throughout this document each major conclusion is anchored, wherever possible, on groups outside<\/em> that cluster: nephrology teams in Iran and Brazil, the UNSW exercise-science group in Australia, and the Forschungszentrum J\u00fclich neuroscience institute in Germany. Every reference carries a tag: INDEPENDENT<\/span> ISSN-CLUSTER<\/span> COMMERCIAL<\/span>. Where only industry-adjacent evidence exists \u2014 the skin section is the clearest case \u2014 the text says so plainly.<\/p>\n <\/div>\n<\/section>\n<section id=\"pyramid\">\n The organising figure<\/span>\n <h2>Where creatine\u2019s claims sit on the certainty ladder<\/h2>\n The tier ladder keeps the parent project\u2019s grammar in a more legible form: bar length encodes evidentiary weight, colour depth encodes certainty<\/strong>, and the bottom rung is deliberately short because it is where arguments live, not where effects are. What is unusual about creatine is that a fifth stratum is needed below the usual contested tier \u2014 a debunked shelf, because several of the most widely believed claims about creatine (kidney destruction, dehydration, hair loss, steroid equivalence) have been tested and have failed.<\/p>\n\n <figure aria-label=\"Five-tier certainty ladder for creatine claims\">\n <svg viewBox=\"0 0 940 640\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Certainty ladder for creatine, five tiers, bar length encodes evidentiary weight<\/title>\n\n \n <line x1=\"210\" y1=\"46\" x2=\"900\" y2=\"46\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <polygon points=\"900,46 886,39 886,53\" fill=\"#16232B\"\/>\n <text x=\"210\" y=\"34\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">BAR LENGTH = EVIDENTIARY WEIGHT (participants \u00d7 replications)<\/text>\n\n \n <line x1=\"40\" y1=\"70\" x2=\"40\" y2=\"600\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <polygon points=\"40,600 33,586 47,586\" fill=\"#16232B\"\/>\n <text x=\"30\" y=\"335\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\" transform=\"rotate(-90 30 335)\" text-anchor=\"middle\">CERTAINTY DECREASES \u2193 \u00b7 colour ramp #093644 \u2192 #A63525<\/text>\n\n \n <rect x=\"70\" y=\"70\" width=\"130\" height=\"92\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"135\" y=\"106\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 1<\/text>\n <text x=\"135\" y=\"128\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">HIGH<\/text>\n <rect x=\"210\" y=\"70\" width=\"690\" height=\"26\" fill=\"#093644\"\/>\n <text x=\"210\" y=\"118\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Replicated RCTs & tracer-method meta-analyses<\/text>\n <text x=\"210\" y=\"138\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">creatinine-rise-without-injury artifact \u00b7 safety 3\u20135 g\/d in healthy adults \u00b7<\/text>\n <text x=\"210\" y=\"156\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">repeated-sprint strength \u00b7 no dehydration\/cramping causation<\/text>\n\n \n <rect x=\"70\" y=\"180\" width=\"130\" height=\"92\" fill=\"#14556E\" rx=\"3\"\/>\n <text x=\"135\" y=\"216\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 2<\/text>\n <text x=\"135\" y=\"238\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">MODERATE<\/text>\n <rect x=\"210\" y=\"180\" width=\"545\" height=\"26\" fill=\"#14556E\"\/>\n <text x=\"210\" y=\"228\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Consistent meta-analytic signal, confounds known<\/text>\n <text x=\"210\" y=\"248\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">lean mass +1.0\u20131.4 kg pooled (water-confounded; UNSW dissent) \u00b7 cognition<\/text>\n <text x=\"210\" y=\"266\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">under metabolic stress \u00b7 women\u2019s strength with training<\/text>\n\n \n <rect x=\"70\" y=\"290\" width=\"130\" height=\"92\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"135\" y=\"326\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 3<\/text>\n <text x=\"135\" y=\"348\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">EMERGING<\/text>\n <rect x=\"210\" y=\"290\" width=\"400\" height=\"26\" fill=\"#3F6B7E\"\/>\n <text x=\"210\" y=\"338\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Small trials, plausible mechanism<\/text>\n <text x=\"210\" y=\"358\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">menopause muscle\/bone \u00b7 depression augmentation \u00b7 single-dose brain rescue \u00b7<\/text>\n <text x=\"210\" y=\"376\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">dietary-insufficiency epidemiology<\/text>\n\n \n <rect x=\"70\" y=\"400\" width=\"130\" height=\"92\" fill=\"#96600B\" rx=\"3\"\/>\n <text x=\"135\" y=\"436\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 4<\/text>\n <text x=\"135\" y=\"458\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">CONTESTED<\/text>\n <rect x=\"210\" y=\"400\" width=\"260\" height=\"26\" fill=\"#96600B\"\/>\n <text x=\"210\" y=\"448\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#16232B\">Contested or insufficient evidence<\/text>\n <text x=\"210\" y=\"468\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">proposed DRIs \u00b7 hypertrophy at 5 g\/d \u00b7 pregnancy use \u00b7 pre-existing CKD \u00b7<\/text>\n <text x=\"210\" y=\"486\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">topical skin claims (commercial)<\/text>\n\n \n <rect x=\"70\" y=\"510\" width=\"130\" height=\"92\" fill=\"#A63525\" rx=\"3\"\/>\n <text x=\"135\" y=\"546\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"800\" font-size=\"17\" fill=\"#FFFFFF\">TIER 5<\/text>\n <text x=\"135\" y=\"568\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12\" fill=\"#FFFFFF\">DEBUNKED<\/text>\n <rect x=\"210\" y=\"510\" width=\"130\" height=\"26\" fill=\"#A63525\"\/>\n <text x=\"210\" y=\"558\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#95291F\">Tested and failed<\/text>\n <text x=\"210\" y=\"578\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#95291F\">kidney destruction \u00b7 hair loss \u00b7 dehydration \u00b7 steroid claims \u00b7<\/text>\n <text x=\"210\" y=\"596\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#95291F\">mandatory loading \u00b7 \u201cwomen get bulky\u201d<\/text>\n <\/svg>\n <figcaption>Fig. 1 \u2014 The creatine certainty ladder.<\/b> Bar length encodes evidentiary weight; colour depth encodes certainty, descending from replicated-RCT territory to the debunked shelf. Tier assignments are argued claim-by-claim in the sections below, each with effect sizes, sample sizes and funding tags. Note the inversion versus folklore: the claims the public fears most (kidneys, hair, dehydration) sit at the debunked end; the claim the industry sells hardest (extra muscle at 5 g\/day) sits one tier lower than commonly assumed.<\/figcaption>\n <\/figure>\n<\/section>\n\n<section id=\"requirement\">\n Physiology first<\/span>\n <h2>How much does a body actually need?<\/h2>\n The gym-culture \u201crequirement\u201d of 5 g\/day is a supplementation dose, not a biological need<\/strong> \u2014 the first popular belief to challenge. Physiologically, total daily turnover is about 2 g\/day<\/span> in a typical adult, met roughly half-and-half by endogenous synthesis and diet (Brosnan & Brosnan 2016; Brosnan 2011). Creatine is a non-proteinogenic amino-acid derivative built from three amino acids: arginine + glycine<\/strong> (via AGAT in kidney, pancreas and liver, forming guanidinoacetate) then methylated by methionine<\/strong> as S-adenosylmethionine (via GAMT, mainly hepatic). That last step is expensive \u2014 creatine synthesis consumes on the order of ~40%<\/span> of the body\u2019s SAMe methylation budget, which is why the precursor amino acids matter as much as creatine itself, and why low-protein diets quietly strain the system.<\/p>\n\n <figure aria-label=\"Daily creatine budget diagram\">\n <svg viewBox=\"0 0 940 400\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Daily creatine budget: losses, synthesis and dietary supply<\/title>\n \n <text x=\"30\" y=\"34\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"16\" fill=\"#16232B\">DAILY CREATINE BUDGET (reference 75 kg man \/ 60 kg woman)<\/text>\n\n \n <rect x=\"30\" y=\"70\" width=\"300\" height=\"112\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"46\" y=\"98\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">ENDOGENOUS SYNTHESIS \u2248 73%<\/text>\n <text x=\"46\" y=\"122\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">arginine + glycine \u2014AGAT\u2192 GAA<\/text>\n <text x=\"46\" y=\"140\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">GAA + methionine\/SAMe \u2014GAMT\u2192 creatine<\/text>\n <text x=\"46\" y=\"164\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#B9CDD6\">consumes ~40% of SAMe methylation budget<\/text>\n\n \n <rect x=\"30\" y=\"196\" width=\"300\" height=\"96\" fill=\"#14556E\" rx=\"3\"\/>\n <text x=\"46\" y=\"224\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">DIET \u2248 27% \u00b7 a \u201ccarninutrient\u201d<\/text>\n <text x=\"46\" y=\"248\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">meat, fish, dairy only \u00b7 plants: 0 g<\/text>\n <text x=\"46\" y=\"266\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#DCE7EC\">US adult mean intake 1.38 g\/d; 42.8% <1 g\/d<\/text>\n\n \n <line x1=\"330\" y1=\"126\" x2=\"430\" y2=\"180\" stroke=\"#093644\" stroke-width=\"3\"\/>\n <line x1=\"330\" y1=\"244\" x2=\"430\" y2=\"200\" stroke=\"#14556E\" stroke-width=\"3\"\/>\n <polygon points=\"430,180 418,170 420,186\" fill=\"#093644\"\/>\n <polygon points=\"430,200 418,196 421,210\" fill=\"#14556E\"\/>\n\n \n <rect x=\"436\" y=\"112\" width=\"230\" height=\"150\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"551\" y=\"146\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">TOTAL BODY POOL<\/text>\n <text x=\"551\" y=\"170\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">~120\u2013130 mmol\/kg dry muscle<\/text>\n <text x=\"551\" y=\"190\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">~95% in skeletal muscle<\/text>\n <text x=\"551\" y=\"210\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">rest: brain, heart, retina,<\/text>\n <text x=\"551\" y=\"228\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#E4E9EC\">testes, blood<\/text>\n\n \n <line x1=\"666\" y1=\"187\" x2=\"760\" y2=\"187\" stroke=\"#95291F\" stroke-width=\"3\"\/>\n <polygon points=\"760,187 748,180 748,194\" fill=\"#95291F\"\/>\n\n \n <rect x=\"764\" y=\"120\" width=\"150\" height=\"134\" fill=\"#95291F\" rx=\"3\"\/>\n <text x=\"839\" y=\"150\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13.5\" fill=\"#FFFFFF\">IRREVERSIBLE LOSS<\/text>\n <text x=\"839\" y=\"174\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#F4DEDA\">\u2192 creatinine \u2192 urine<\/text>\n <text x=\"839\" y=\"200\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#F4DEDA\">men 20 mg\/kg\/d<\/text>\n <text x=\"839\" y=\"218\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#F4DEDA\">women 15 mg\/kg\/d<\/text>\n\n \n <rect x=\"30\" y=\"316\" width=\"884\" height=\"1.5\" fill=\"#BCC7CD\"\/>\n <text x=\"30\" y=\"348\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#4A5B66\">TURNOVER \u2248 2 g\/d \u00b7 proposed Adequate Intake (Ostojic 2026, unratified): men 5.4 mg\/kg\/d \u2248 400 mg \u00b7 women 4.1 mg\/kg\/d \u2248 240 mg<\/text>\n <text x=\"30\" y=\"372\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#95291F\">SUPPLEMENT DOSES sit 8\u201350\u00d7 above the proposed dietary AI: maintenance 3\u20135 g\/d \u00b7 loading 20 g\/d (optional, never mandatory)<\/text>\n <\/svg>\n <figcaption>Fig. 2 \u2014 The daily creatine budget.<\/b> Loss estimates and the 73\/27 synthesis-to-diet split are from the 2026 DRI proposal (Ostojic, Nutrition Reviews<\/i>); pool size and distribution from Candow et al. 2025; intake distributions from NHANES analyses. The DRI values are a serious proposal from a single researcher, not a ratified reference \u2014 placed at Tier 4 accordingly.<\/figcaption>\n <\/figure>\n\n <div class=\"stat-row\">\n <div class=\"stat\">\u2248 2 g\/d<\/span>total physiological turnover, adult omnivore (Brosnan 2016)<\/span><\/div>\n <div class=\"stat\">2.7\u00d7<\/span>precursor-derived synthesis capacity vs dietary creatine intake, NHANES III, n = 29,945 (Nedeljkovic & Ostojic 2025)<\/span><\/div>\n <div class=\"stat contest\">42.8%<\/span>of US adults below 1 g\/d dietary creatine; ~60% of 4,291 children, 17% consuming zero (Ostojic 2021)<\/span><\/div>\n <div class=\"stat flag\">0 g<\/span>dietary creatine on vegan diets \u2014 a carninutrient absent from all plant foods; vegetarians show measurably lower muscle stores<\/span><\/div>\n <\/div>\n\n Challenge to the popular belief:<\/strong> \u201ceveryone needs to supplement\u201d and \u201cnobody needs to supplement\u201d are both wrong. A healthy omnivore synthesises and eats enough to hold the pool. The genuinely exposed groups are vegans\/vegetarians (zero dietary supply), older adults with low meat intake, and possibly people on chronic low-protein diets \u2014 for whom the precursor amino acids (glycine, arginine, methionine) are also the constraint. NHANES associations linking <1 g\/day intake to higher all-cause mortality (HR 0.85 for \u22651 g\/d, 95% CI 0.72\u20131.00, 19.8-yr follow-up) are observational Tier-3 evidence at best: recall-based intake, single 24-h snapshots, and meat intake as an obvious confounder.<\/p>\n<\/section>\n\n<section id=\"muscle\">\n Muscles & strength<\/span>\n <h2>The biggest pro-creatine belief, put on trial<\/h2>\n Here the strongest independent<\/em> evidence pushes against the marketing, not for it. The 2025 UNSW randomized trial (Desai, Pandit \u2026 Hagstrom, Nutrients<\/i>) did what almost no prior trial had done: it inserted a 7-day non-exercise wash-in<\/strong> before training began, so the fluid effect of creatine could be separated from actual tissue growth. Sixty-three adults (34 women, 29 men, 31 \u00b1 8 y) took 5 g\/day or served as controls, then both groups trained identically for 12 weeks.<\/p>\n\n <figure aria-label=\"UNSW trial lean body mass timeline\">\n <svg viewBox=\"0 0 940 420\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>UNSW 2025 trial: lean body mass change over wash-in and training phases<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">LEAN BODY MASS CHANGE (kg, DXA) \u2014 UNSW RCT, n=63, 5 g\/day vs control<\/text>\n\n \n <line x1=\"90\" y1=\"330\" x2=\"880\" y2=\"330\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <line x1=\"90\" y1=\"70\" x2=\"90\" y2=\"330\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n \n <text x=\"78\" y=\"334\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">0<\/text>\n <line x1=\"86\" y1=\"245\" x2=\"880\" y2=\"245\" stroke=\"#BCC7CD\" stroke-width=\"1\"\/>\n <text x=\"78\" y=\"249\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">+1<\/text>\n <line x1=\"86\" y1=\"160\" x2=\"880\" y2=\"160\" stroke=\"#BCC7CD\" stroke-width=\"1\"\/>\n <text x=\"78\" y=\"164\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">+2<\/text>\n <line x1=\"86\" y1=\"75\" x2=\"880\" y2=\"75\" stroke=\"#BCC7CD\" stroke-width=\"1\"\/>\n <text x=\"78\" y=\"79\" text-anchor=\"end\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">+3<\/text>\n\n \n <line x1=\"300\" y1=\"70\" x2=\"300\" y2=\"330\" stroke=\"#7E8D96\" stroke-width=\"1\" stroke-dasharray=\"5 5\"\/>\n <text x=\"195\" y=\"356\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">WASH-IN \u00b7 7 d \u00b7 no exercise<\/text>\n <text x=\"590\" y=\"356\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">RESISTANCE TRAINING \u00b7 12 wk \u00b7 3 sessions\/wk<\/text>\n\n \n <polyline points=\"90,330 300,287 860,117\" fill=\"none\" stroke=\"#093644\" stroke-width=\"4\"\/>\n <circle cx=\"300\" cy=\"287\" r=\"6\" fill=\"#093644\"\/>\n <circle cx=\"860\" cy=\"117\" r=\"6\" fill=\"#093644\"\/>\n \n <polyline points=\"90,330 300,330 860,160\" fill=\"none\" stroke=\"#96600B\" stroke-width=\"4\"\/>\n <circle cx=\"300\" cy=\"330\" r=\"6\" fill=\"#96600B\"\/>\n <circle cx=\"860\" cy=\"160\" r=\"6\" fill=\"#96600B\"\/>\n\n \n <text x=\"312\" y=\"278\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#093644\">+0.51 \u00b1 1.79 kg before any training (p=0.03)<\/text>\n <text x=\"312\" y=\"296\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#95291F\">\u2014 interpreted as fluid, not muscle<\/text>\n <text x=\"640\" y=\"100\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#093644\">creatine 5 g\/d<\/text>\n <text x=\"640\" y=\"196\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#96600B\">control<\/text>\n <text x=\"520\" y=\"240\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13.5\" fill=\"#16232B\">training gain \u2248 2 kg in BOTH groups<\/text>\n <text x=\"520\" y=\"258\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">between-group difference p = 0.71 (null)<\/text>\n <\/svg>\n <figcaption>Fig. 3 \u2014 The wash-in that changed the question.<\/b> Values from Desai et al. 2025 (10.3390\/nu17061081), independent of supplement funding at design level. The early gain \u2014 larger in women (+0.59 \u00b1 1.61 kg, p=0.04) \u2014 appeared before a single training session<\/b>, which is why the authors read it as fluid. Senior author Hagstrom: the benefits of creatine \u201cmay have been overestimated in the past, due to methodological problems with previous studies,\u201d and 5 g\/day \u201cis not enough if you\u2019re taking it for the purposes of building muscle.\u201d Prior no-wash-in trials credited creatine with ~1 kg extra muscle over 4\u201312 weeks.<\/figcaption>\n <\/figure>\n\n Against the UNSW null stands the pooled literature: a 2025 dose\u2013response meta-analysis of 61 trials<\/span> found creatine increased fat-free mass by +1.39 kg (95% CI 1.07\u20131.70)<\/span> and body mass by +0.89 kg<\/span>, with no effect on fat mass META<\/span>. But nearly all constituent trials used DXA or similar methods that cannot distinguish intracellular water from contractile tissue<\/strong> \u2014 exactly the confound UNSW isolated. At the elite end, an independent Spanish RCT in 23 professional U23 cyclists found 20 g\/day for 6 days produced no consistent benefit<\/strong> on recovery, body composition or performance RCT<\/span>. And in frail older adults, two pooled trials (n=106, ~6 g\/day, 14\u201316 weeks of training) showed training worked but creatine added nothing.<\/p>\n\n <div class=\"callout blue\">\n Honest synthesis \u2014 Tier 1 vs Tier 2 split<\/span>\n Tier 1 (keep):<\/strong> creatine reliably raises muscle phosphocreatine and improves repeated short high-intensity efforts \u2014 strength and power capacity across hundreds of trials since the 1990s. Tier 2 (demote):<\/strong> the lean-mass<\/em> benefit at 3\u20135 g\/day is smaller than folklore claims and partly a water artifact; the UNSW authors suggest ~10 g\/day may be the hypertrophy-relevant dose, but that has not yet been tested in a dedicated RCT. The popular belief \u201ccreatine builds muscle by itself\u201d fails; \u201ccreatine lets you train harder, and training builds muscle\u201d survives.<\/p>\n <\/div>\n<\/section>\n<section id=\"kidney\">\n The kidney question<\/span>\n <h2>Kidneys: the myth runs both ways \u2014 and both extremes fail<\/h2>\n Gym forums say creatine destroys kidneys; supplement marketing says it is \u201cproven completely safe.\u201d The 2025\u20132026 nephrology literature \u2014 largely from groups with no supplement-industry ties<\/strong> \u2014 supports neither extreme. The mechanistic core is an artifact: supplemental creatine degrades non-enzymatically to creatinine, the very molecule used to estimate kidney function<\/strong>. Serum creatinine rises, creatinine-based eGFR falls, and no injury has occurred.<\/p>\n\n <figure aria-label=\"Creatinine artifact chart\">\n <svg viewBox=\"0 0 940 430\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Kidney outcomes under creatine: creatinine-based estimates versus tracer-measured GFR<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">SAME KIDNEYS, TWO MEASUREMENTS \u2014 meta-analysis of 26 RCTs, n=1,036 (Int Urol Nephrol 2026)<\/text>\n\n \n <line x1=\"470\" y1=\"70\" x2=\"470\" y2=\"340\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <text x=\"470\" y=\"360\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">0 = no change vs placebo<\/text>\n\n \n <text x=\"60\" y=\"112\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Serum creatinine<\/text>\n <rect x=\"470\" y=\"92\" width=\"150\" height=\"34\" fill=\"#A63525\"\/>\n <text x=\"632\" y=\"115\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#95291F\">+0.14 mg\/dL (95% CI 0.05\u20130.22) \u2014 RISES<\/text>\n\n \n <text x=\"60\" y=\"154\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">eGFR \u2014 creatinine-based estimate<\/text>\n <rect x=\"290\" y=\"162\" width=\"180\" height=\"34\" fill=\"#A63525\"\/>\n <text x=\"60\" y=\"204\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#95291F\">\u221210.75 mL\/min \u2014 \u201cFALLS\u201d (artifact of the molecule being measured)<\/text>\n\n \n <text x=\"60\" y=\"252\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">GFR \u2014 Cr-EDTA tracer (true measurement)<\/text>\n <rect x=\"470\" y=\"232\" width=\"66\" height=\"34\" fill=\"#093644\"\/>\n <text x=\"548\" y=\"255\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#0C3A4D\">+5.89 mL\/min (95% CI \u22120.30 to 12.08, p=0.06) \u2014 NO DECLINE<\/text>\n\n \n <text x=\"60\" y=\"294\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Serum urea \u00b7 albuminuria \u00b7 proteinuria \u00b7 urinary creatinine<\/text>\n <rect x=\"462\" y=\"302\" width=\"16\" height=\"34\" fill=\"#3F6B7E\"\/>\n <text x=\"490\" y=\"325\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#3F6B7E\">no significant differences \u2014 injury markers silent<\/text>\n\n <text x=\"30\" y=\"394\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">Concordant independent meta-analyses: BMC Nephrology 2025 (21 studies; creatinine MD +0.07, GFR n.s.) \u00b7<\/text>\n <text x=\"30\" y=\"412\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#4A5B66\">J Renal Nutrition 2019 (Brazil; \u201cdoes not induce renal damage\u201d) \u00b7 J Renal Nutrition 2026 (Tsiaras; creatinine +0.13 mg\/dL, 19 RCTs)<\/text>\n <\/svg>\n <figcaption>Fig. 4 \u2014 The creatinine artifact, quantified.<\/b> When kidney function is measured with a tracer that does not depend on creatinine (Cr-EDTA), the \u201cdecline\u201d vanishes. The 2026 meta-analysis authors: findings \u201clikely reflect altered creatinine metabolism rather than kidney injury.\u201d All four meta-analyses are from nephrology\/renal-nutrition groups independent of the ISSN cluster.<\/figcaption>\n <\/figure>\n\n What survives scrutiny on the cautious side:<\/strong> nobody has run long RCTs in people with pre-existing chronic kidney disease \u2014 trials in type 2 diabetics, peripheral artery disease and hemodialysis patients show no injury signal, but they are short and small. Rare case reports (including one acute tubular necrosis) exist but are confounded and number in single digits against tens of thousands of trial participants. The one real-world harm<\/em> is diagnostic: an artifactually raised creatinine can trigger misdiagnosis, unnecessary work-ups, or wrongly adjusted drug doses. Anyone supplementing should tell their physician; confirmation should use cystatin C or measured GFR, not creatinine-based eGFR.<\/strong><\/p>\n\n <h3>The long-term record, trial by trial \u2014 does chronic intake damage the kidney?<\/h3>\n To answer the long-term question directly, here is every substantive long-duration human dataset located in this research pass, with method quality noted. The pattern is consistent: no study using an injury-capable method has detected kidney damage in people with healthy kidneys<\/strong>, across exposures from 12 weeks to 5 years and doses to ~10 g\/day \u2014 while the honest gaps (pre-existing CKD, decades-long unsupervised use) remain unfilled.<\/p>\n\n <table class=\"wrapok\">\n <caption>Long-duration & gold-standard-method kidney studies (independent groups unless noted)<\/caption>\n <thead><tr><th>Study<\/th><th>Population & exposure<\/th><th>Method<\/th><th>Result<\/th><\/tr><\/thead>\n <tbody>\n <tr><td class=\"tnum\">Poortmans & Francaux 1999 IND<\/span><\/td><td>Healthy athletes, creatine use 10 months \u2013 5 years<\/strong> vs controls<\/td><td>Creatinine, urea & albumin clearances<\/td><td class=\"good\">No differences in GFR, tubular reabsorption, or membrane permeability \u2014 the foundational long-term dataset (limits: retrospective, non-randomized)<\/td><\/tr>\n <tr><td class=\"tnum\">Kreider et al. 2003 ISSN<\/span><\/td><td>College athletes, up to 21 months<\/strong>, ~5\u201310 g\/d<\/td><td>69 clinical health markers<\/td><td class=\"good\">No significant differences vs non-users<\/td><\/tr>\n <tr><td class=\"tnum\">Gualano et al. 2008 IND \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Healthy adults, 12 wk, ~10 g\/d, RCT<\/td><td>Cystatin C<\/strong> (creatinine-independent)<\/td><td class=\"good\">Cystatin C unchanged (actually slightly decreased) \u2014 no injury<\/td><\/tr>\n <tr><td class=\"tnum\">Lugaresi et al. 2013 IND \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Resistance-trained adults on a high-protein diet<\/strong> (\u22651.2 g\/kg\/d), 12 wk, 20\u21925 g\/d, RCT<\/td><td>\u2075\u00b9Cr-EDTA clearance<\/strong> (tracer gold standard)<\/td><td class=\"good\">No change in measured GFR \u2014 the \u201ccreatine + high protein wrecks kidneys\u201d stack claim fails its direct test<\/td><\/tr>\n <tr><td class=\"tnum\">Gualano et al. 2011 IND<\/span><\/td><td>Type 2 diabetics<\/strong> (renally vulnerable), 12 wk, RCT<\/td><td>\u2075\u00b9Cr-EDTA clearance<\/td><td class=\"good\">No impairment<\/td><\/tr>\n <tr><td class=\"tnum\">Neves et al. 2011 IND<\/span><\/td><td>Postmenopausal women<\/strong>, RCT<\/td><td>Measured GFR<\/td><td class=\"good\">No effect \u2014 female-specific renal reassurance<\/td><\/tr>\n <tr><td class=\"tnum\">Bender et al. 2008 IND<\/span><\/td><td>Parkinson\u2019s patients, 2 years<\/strong>, 4 g\/d, placebo-controlled<\/td><td>Renal markers incl. cystatin C<\/td><td class=\"good\">No significant changes after 2 years of continuous use<\/td><\/tr>\n <tr><td class=\"tnum\">Gualano et al. 2010 IND<\/span><\/td><td>Young man with a single kidney<\/strong> and mildly reduced GFR, 35 d, 20\u21925 g\/d<\/td><td>Measured GFR<\/td><td class=\"mid\">Case study: GFR unchanged \u2014 reassuring but n=1, not generalizable<\/td><\/tr>\n <tr><td class=\"tnum\">Hemodialysis subgroup, 2026 meta IND<\/span><\/td><td>Dialysis patients (kidneys already failed)<\/td><td>Pooled RCT markers<\/td><td class=\"mid\">Serum creatinine rose (expected); serum urea fell<\/em>; no injury signal \u2014 but this is therapy research, not license for CKD self-supplementation<\/td><\/tr>\n <tr><td class=\"tnum\">Longobardi et al. 2023 IND<\/span><\/td><td>Narrative review, \u201crequiem for creatine-induced kidney failure?\u201d<\/td><td>All case reports re-examined<\/td><td class=\"good\">Nearly every published \u201ccreatine kidney failure\u201d case involved confounders: pre-existing disease, anabolic steroids, NSAIDs, dehydration protocols, or unverified multi-ingredient products<\/td><\/tr>\n <\/tbody>\n <\/table>\n Long-term verdict, stated plainly:<\/strong> at 3\u201310 g\/day, across every controlled study up to 2 years and observational use to 5 years, chronic intake has not damaged healthy kidneys by any creatinine-independent measure. What long-term intake does<\/em> do, permanently while you take it, is elevate serum creatinine \u2014 a lab artifact that will follow you into every routine blood panel. The remaining unknowns are pre-existing CKD stages 1\u20135 (zero long-term RCTs \u2014 the 2026 meta-analysis authors note this gap explicitly) and unsupervised decades-scale use. If you have one kidney, reduced GFR, diabetes with nephropathy, or take nephrotoxic drugs (NSAIDs chronically, some antibiotics), supplement only with physician monitoring.<\/p>\n<\/section>\n\n<section id=\"water\">\n Water<\/span>\n <h2>\u201cDrink gallons or you\u2019ll dehydrate\u201d is backwards<\/h2>\n The osmotic logic is real but points the opposite direction from the myth. Creatine pulls water into<\/strong> muscle cells: loading (20 g\/day) measurably raises total and intracellular body water for days, which is most of the famous 1\u20132 kg scale jump. Over 5\u201310-week training studies, total body water relative to muscle mass<\/em> shows no lasting distortion. On dehydration and cramping \u2014 a belief once endorsed even by the ACSM in the early 2000s on speculation, not data \u2014 the controlled literature finds no causation, and several heat-stress studies found creatine users had lower core temperatures and better fluid retention<\/strong> than placebo; older athlete cohorts reported cramping reduced, not increased. The Brazilian (Gualano-group) 2025 safety review in Frontiers in Nutrition<\/i> concludes hydration and thermoregulation are unaffected.<\/p>\n <div class=\"callout blue\">\n Practical translation<\/span>\n Normal thirst-guided fluid intake suffices. The \u201cgallon rule\u201d is folklore; forced water-loading has no evidence base and its only reliable effect is inconvenience. The intracellular water shift is also why first-week scale weight is meaningless as a muscle measure \u2014 see Fig. 3.<\/p>\n <\/div>\n<\/section>\n\n<section id=\"liver\">\n Liver<\/span>\n <h2>Liver: no credible harm signal \u2014 and an inverted association<\/h2>\n No meta-analysis or long-term trial detects hepatotoxicity at studied doses. Dedicated hepatic-marker meta-analyses (Alizadeh 2022, Sports Medicine \u2013 Open<\/i>; Kashi 2024, Nutrition Research Reviews<\/i>) find liver enzymes unchanged; a 52-week trial at 5 g\/day in older adults kept enzymes stable; adolescent and youth-athlete cohorts through full competitive seasons kept ALT\/AST within reference ranges with no hepatotoxicity signal META<\/span> RCT<\/span>. The inversion worth reporting: NHANES analyses associate low dietary<\/em> creatine (<0.95\u20131 g\/day) with higher<\/em> risk of liver conditions \u2014 observational only COHORT<\/span>, meat-intake-confounded, but it flips the folk narrative. The honest gap: people with existing liver disease are nearly absent from trials; since the liver hosts the GAMT step of synthesis, severe hepatic impairment is a legitimate reason for medical supervision, not a documented creatine harm.<\/p>\n<\/section>\n\n<section id=\"skin\">\n Skin \u2014 commercial corner<\/span>\n <h2>Skin: the weakest, most industry-owned claim in the file<\/h2>\n This is where the independent-versus-commercial filter matters most. The frequently cited anti-wrinkle findings come from topical cosmetic formulations studied largely by Beiersdorf (Nivea) scientists<\/strong>: a single-centre controlled study of 43 men applying a cream containing creatine plus guarana and glycerol<\/em> reported firmness and wrinkle improvements at six weeks (Peirano 2011, J Cosmetic Dermatology<\/i>) COMMERCIAL<\/span>; earlier in-house work reported photoprotection and stimulated collagen, glycosaminoglycan and ceramide synthesis (Lenz 2005) COMMERCIAL<\/span>. Mechanistically plausible \u2014 skin\u2019s creatine-kinase energy system genuinely declines with age and oxidative stress \u2014 but these are multi-ingredient, industry-run, single-centre studies, never independently replicated at scale.<\/p>\n <div class=\"callout amber\">\n Verdict<\/span>\n Oral creatine for skin: unproven.<\/strong> There is no direct evidence that 3\u20135 g\/day orally produces measurable changes in skin quality \u2014 every clinical result comes from creams and serums. Topical creatine: low-certainty, commercially generated Tier 4 evidence.<\/strong> Claims of \u201ccreatine causes acne\u201d are equally unsupported in either direction. If skin is the goal, the evidence-backed money goes to photoprotection and retinoids, not creatine.<\/p>\n <\/div>\n<\/section>\n\n<section id=\"brain\">\n Brain, cognition & mood<\/span>\n <h2>The strongest genuinely new post-2015 story<\/h2>\n The brain burns ~20% of the body\u2019s energy at 2% of its mass, and brain creatine \u2014 unlike muscle \u2014 responds slowly and modestly to supplementation. The most striking independent finding comes from a German government research institute (Forschungszentrum J\u00fclich): in a randomized double-blind crossover trial, a single oral dose of 0.35 g\/kg<\/strong> during 21 hours of sleep deprivation raised brain PCr\/Pi, prevented a pH drop, and improved cognitive performance and processing speed \u2014 partially reversing fatigue-related deterioration (Gordji-Nejad 2024, Scientific Reports<\/i>, n=15) RCT<\/span> INDEPENDENT<\/span>. A 2026 replication at a lower 0.2 g\/kg<\/strong> dose (n=29) still mitigated deterioration in logic, numerical tasks, language-processing speed and psychomotor vigilance \u2014 with the authors noting the short-term-memory effect appears dose-dependent.<\/p>\n\n <figure aria-label=\"Cognition meta-analysis forest-style chart\">\n <svg viewBox=\"0 0 940 380\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Meta-analytic effects of creatine on cognitive domains<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">COGNITIVE DOMAINS \u2014 16 RCTs, n=492, ages 20.8\u201376.4 (Xu 2024, Frontiers in Nutrition)<\/text>\n <text x=\"30\" y=\"52\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">standardised mean difference; bars scaled |SMD| \u2014 negative time scores = faster = benefit<\/text>\n\n <line x1=\"360\" y1=\"80\" x2=\"360\" y2=\"330\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n <text x=\"360\" y=\"350\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">0<\/text>\n\n <text x=\"40\" y=\"112\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Memory<\/text>\n <rect x=\"360\" y=\"94\" width=\"124\" height=\"30\" fill=\"#093644\"\/>\n <text x=\"494\" y=\"115\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#0C3A4D\">SMD +0.31 (0.18\u20130.44) \u2014 significant<\/text>\n\n <text x=\"40\" y=\"172\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Attention time<\/text>\n <rect x=\"360\" y=\"154\" width=\"124\" height=\"30\" fill=\"#14556E\"\/>\n <text x=\"494\" y=\"175\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#14556E\">SMD \u22120.31 (\u22120.58 to \u22120.03) \u2014 faster<\/text>\n\n <text x=\"40\" y=\"232\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Processing speed<\/text>\n <rect x=\"360\" y=\"214\" width=\"204\" height=\"30\" fill=\"#14556E\"\/>\n <text x=\"574\" y=\"235\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#14556E\">SMD \u22120.51 (\u22121.01 to \u22120.01) \u2014 faster, wide CI<\/text>\n\n <text x=\"40\" y=\"292\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Overall cognition \u00b7 executive function<\/text>\n <rect x=\"352\" y=\"274\" width=\"16\" height=\"30\" fill=\"#96600B\"\/>\n <text x=\"380\" y=\"295\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#96600B\">not significant \u2014 no global IQ effect<\/text>\n <\/svg>\n <figcaption>Fig. 5 \u2014 Small, domain-specific, condition-dependent.<\/b> Effects concentrate where brain energy supply is strained: sleep deprivation, vegetarians\/vegans (lowest baseline stores, largest gains since Rae 2003), older adults, heavy mental fatigue. In rested young omnivores the system is near-saturated and effects approach zero. Depression: several small RCTs of 3\u20135 g\/day added to SSRIs show faster, larger improvement \u2014 most consistently in women \u2014 Tier 3 emerging, not yet definitive.<\/figcaption>\n <\/figure>\n<\/section>\n\n<section id=\"women\">\n Women\u2019s health<\/span>\n <h2>Women: real physiology, thinner evidence than the headlines imply<\/h2>\n The physiology is distinct and understudied: females carry 70\u201380% lower<\/span> endogenous creatine stores than males yet ~10% higher<\/em> resting intramuscular concentrations, and estrogen\/progesterone modulate AGAT\/GAMT expression and creatine-kinase kinetics across the menstrual cycle, pregnancy and menopause (Smith-Ryan 2021; Ellery 2016). That makes supplementation plausibly more<\/em> relevant at specific life stages \u2014 and also makes early performance studies that ignored cycle phase harder to interpret.<\/p>\n\n <figure aria-label=\"Women's lifespan evidence map\">\n <svg viewBox=\"0 0 940 330\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Evidence strength for creatine across the female lifespan<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">EVIDENCE ACROSS THE FEMALE LIFESPAN \u2014 colour = certainty tier<\/text>\n\n \n <line x1=\"60\" y1=\"230\" x2=\"900\" y2=\"230\" stroke=\"#16232B\" stroke-width=\"2\"\/>\n\n \n <rect x=\"60\" y=\"90\" width=\"200\" height=\"120\" fill=\"#14556E\" rx=\"3\"\/>\n <text x=\"160\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">MENSTRUATING YEARS<\/text>\n <text x=\"160\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#DCE7EC\">strength & performance \u2191<\/text>\n <text x=\"160\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#DCE7EC\">with training \u00b7 TIER 2<\/text>\n <text x=\"160\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#B9CDD6\">cycle-controlled trials only recent<\/text>\n\n \n <rect x=\"280\" y=\"90\" width=\"190\" height=\"120\" fill=\"#A63525\" rx=\"3\"\/>\n <text x=\"375\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">PREGNANCY<\/text>\n <text x=\"375\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F4DEDA\">mostly animal models<\/text>\n <text x=\"375\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F4DEDA\">no human RCTs \u00b7 TIER 4\/5<\/text>\n <text x=\"375\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#F4DEDA\">DO NOT EXTRAPOLATE<\/text>\n\n \n <rect x=\"490\" y=\"90\" width=\"190\" height=\"120\" fill=\"#96600B\" rx=\"3\"\/>\n <text x=\"585\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">PERIMENOPAUSE<\/text>\n <text x=\"585\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F3E7D2\">near-empty evidence zone<\/text>\n <text x=\"585\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#F3E7D2\">first small trials 2025 \u00b7 TIER 3\/4<\/text>\n <text x=\"585\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#F3E7D2\">sleep-quality signal, n=15<\/text>\n\n \n <rect x=\"700\" y=\"90\" width=\"200\" height=\"120\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"800\" y=\"118\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#FFFFFF\">POST-MENOPAUSE<\/text>\n <text x=\"800\" y=\"142\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#E4E9EC\">muscle size\/function at high<\/text>\n <text x=\"800\" y=\"160\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11\" fill=\"#E4E9EC\">dose 0.3 g\/kg\/d + training<\/text>\n <text x=\"800\" y=\"184\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"10.5\" fill=\"#E4E9EC\">bone: mixed \u00b7 TIER 2\/3<\/text>\n\n \n <rect x=\"60\" y=\"252\" width=\"840\" height=\"46\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"480\" y=\"272\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">FEMALE-SPECIFIC SAFETY META-ANALYSIS (de Guingand 2020 \u00b7 29 monitored studies \u00b7 n=951)<\/text>\n <text x=\"480\" y=\"290\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">no deaths or serious adverse outcomes \u00b7 total AEs RR 1.24 (0.51\u20132.98) n.s. \u00b7 GI RR 1.09 n.s. \u00b7 weight gain n.s.<\/text>\n <\/svg>\n <figcaption>Fig. 6 \u2014 The female evidence map.<\/b> Sources: Smith-Ryan et al. 2021 & 2025 (lifespan reviews \u2014 ISSN-cluster authorship, flagged), Hall 2025 (peri\/post-menopause quasi-experimental, n=15: lower-body strength \u2191, perimenopausal sleep quality p=0.0181, estradiol unchanged), CONCRET-MENOPA RCT 2025 (n=36: 1.5 g\/day creatine HCl improved reaction time and raised frontal brain creatine +16.4% vs 0.9% placebo), de Guingand 2020 safety meta-analysis (independent, Hudson Institute). Only 9% of all creatine studies to 2020 were female-only.<\/figcaption>\n <\/figure>\n\n <h3>The women\u2019s trial base, paper by paper<\/h3>\n Because the headlines outrun the trials here, the substantive female-specific studies located in this pass are tabulated below. Two things stand out. First, the two largest and longest<\/strong> women\u2019s trials ever run \u2014 both independent \u2014 were bone<\/em> trials, and both were essentially null on bone density. Second, the most consistent positive female-specific signal is not muscle at all: it is depression augmentation and brain energetics<\/strong>, from an independent psychiatry group (Univ. of Utah \/ Seoul) with no supplement-industry stake.<\/p>\n\n <table class=\"wrapok\">\n <caption>Female-specific studies \u2014 design, size, outcome<\/caption>\n <thead><tr><th>Study<\/th><th>Design & population<\/th><th>Dose \/ duration<\/th><th>Outcome<\/th><\/tr><\/thead>\n <tbody>\n <tr><td class=\"tnum\">Chilibeck 2015 IND<\/span><\/td><td>RCT, postmenopausal women + supervised resistance training<\/td><td class=\"tnum\">0.1 g\/kg\/d \u00b7 12 mo<\/td><td class=\"mid\">Femoral-neck BMD loss slowed<\/em> vs placebo \u2014 the hopeful signal that motivated the bigger trial<\/td><\/tr>\n <tr><td class=\"tnum\">Chilibeck 2023 IND<\/span><\/td><td>RCT, n=237<\/strong> postmenopausal women, training + walking, 2 years<\/strong> \u2014 the largest women\u2019s creatine trial ever run<\/td><td class=\"tnum\">0.14 g\/kg\/d (~9.8 g) \u00b7 24 mo<\/td><td class=\"mid\">BMD: null<\/strong> at femoral neck, total hip, lumbar spine. Positive secondaries: femoral-neck section modulus preserved (p=0.0011), buckling ratio improved (p=0.011), 80-m walk faster (p=0.0008), lean mass +1.1 kg in completers. Strength (1RM): no difference<\/td><\/tr>\n <tr><td class=\"tnum\">Sales\/Gualano 2020 IND \u2014 S\u00e3o Paulo<\/span><\/td><td>RCT, n=200<\/strong> postmenopausal women with osteopenia, 2 years<\/strong>, no structured training<\/td><td class=\"tnum\">3 g\/d \u00b7 24 mo<\/td><td class=\"bad\">Null on BMD, bone markers, microarchitecture, falls\/fractures \u2014 and null on lean mass and muscle function<\/em>. Authors: \u201crefutes the long-lasting notion that this supplement alone has osteogenic or anabolic properties.\u201d Safety labs clean throughout<\/td><\/tr>\n <tr><td class=\"tnum\">Postmenopausal meta 2025 IND<\/span><\/td><td>Systematic review + meta-analysis, 2000\u2013Aug 2025, RCTs in women \u226540\u201345<\/td><td class=\"tnum\">various \u22656 wk<\/td><td class=\"mid\">Lean mass pooled +0.37 kg<\/strong>; BMD pooled MD \u2248 0.00 g\/cm\u00b2 \u2014 CIs span no-effect throughout<\/td><\/tr>\n <tr><td class=\"tnum\">Lyoo 2012 IND \u2014 psychiatry<\/span><\/td><td>Double-blind RCT, n=52 women<\/strong> with major depressive disorder, creatine added to escitalopram<\/td><td class=\"tnum\">3\u21925 g\/d \u00b7 8 wk<\/td><td class=\"good\">Faster, larger HAM-D improvement vs SSRI+placebo (reported effect size ~d=1.13); more remissions; good tolerability<\/td><\/tr>\n <tr><td class=\"tnum\">Yoon 2015 IND<\/span><\/td><td>Neuroimaging arm of the same RCT, n=34<\/td><td class=\"tnum\">5 g\/d \u00b7 8 wk<\/td><td class=\"good\">Prefrontal NAA increased vs placebo (d=0.73); rich-club network connectivity normalized \u2014 a mechanism, not just a rating scale<\/td><\/tr>\n <tr><td class=\"tnum\">Kondo 2016 IND \u2014 NIMH-funded<\/span><\/td><td>Dose-ranging RCT, n=33 adolescent females<\/strong>, SSRI-resistant depression<\/td><td class=\"tnum\">2 \/ 4 \/ 10 g\/d \u00b7 8 wk<\/td><td class=\"mid\">Depression scores: no significant difference vs placebo<\/strong>; but brain phosphocreatine rose dose-dependently and correlated with mood improvement \u2014 target engaged, clinical effect unproven in teens<\/td><\/tr>\n <tr><td class=\"tnum\">Hall 2025 IND<\/span><\/td><td>Quasi-experimental, n=15 peri\/postmenopausal + training, 14 wk<\/td><td class=\"tnum\">std dose<\/td><td class=\"mid\">Lower-body strength \u2191; perimenopausal sleep quality \u2191 (p=0.0181); estradiol unchanged \u2014 tiny, non-randomized<\/td><\/tr>\n <tr><td class=\"tnum\">CONCRET-MENOPA 2025 ISSN<\/span><\/td><td>RCT, n=36 peri\/menopausal women<\/td><td class=\"tnum\">0.75\u20131.5 g\/d HCl \u00b7 8 wk<\/td><td class=\"mid\">Reaction time \u2191, frontal brain creatine +16.4% vs 0.9%, lipids improved \u2014 small, non-monohydrate forms<\/td><\/tr>\n <tr><td class=\"tnum\">de Guingand 2020 IND \u2014 Hudson Inst.<\/span><\/td><td>Safety meta-analysis, 29 monitored female-only studies, n=951<\/td><td class=\"tnum\">all doses<\/td><td class=\"good\">No deaths or serious adverse outcomes; total AEs, GI events, weight gain all non-significant vs placebo<\/td><\/tr>\n <tr><td class=\"tnum\">Gordon 2023 ISSN<\/span><\/td><td>Crossover RCT, n=39 active women, both cycle phases<\/td><td class=\"tnum\">20 g\/d loading<\/td><td class=\"mid\">No HRV harm; recovery effects modest; first properly cycle-controlled loading study<\/td><\/tr>\n <tr><td class=\"tnum\">Dickinson 2016 IND<\/span><\/td><td>Retrospective pregnancy cohort, n=287<\/strong><\/td><td class=\"tnum\">dietary only<\/td><td class=\"mid\">Higher maternal urinary creatine associated with higher birthweight centile (+1.23\/\u03bcmol\u00b7L\u207b\u00b9) and birth length \u2014 associational<\/td><\/tr>\n <tr><td class=\"tnum\">de Guingand 2024 (CPO) IND<\/span><\/td><td>Prospective pregnancy cohort, n=282<\/strong>, 5 timepoints + cord\/placenta<\/td><td class=\"tnum\">dietary only<\/td><td class=\"good\">Plasma creatine stable across gestation; synthesis machinery visibly reorganizes (GAA shifts); animal-protein intake tracks plasma creatine; no adverse creatine\u2013growth links<\/td><\/tr>\n <tr><td class=\"tnum\">Naidu 2025 IND \u2014 Monash<\/span><\/td><td>Open-label dose-escalation PK trial, third-trimester women (n=15 total)<\/td><td class=\"tnum\">5 g \u00d71, then 5 g q8h \u00d73 d<\/td><td class=\"mid\">First human supplementation-in-pregnancy data: well tolerated short-term, PK characterized, fetal monitoring unremarkable \u2014 a phase-1-style step, not<\/strong> an efficacy or safety endorsement<\/td><\/tr>\n <tr><td class=\"tnum\">Freeman 2025 IND \u2014 Otago<\/span><\/td><td>Guinea-pig full-term pregnancy safety model<\/td><td class=\"tnum\">0.3 g\/kg\/d<\/td><td class=\"mid\">No fetal-growth or offspring harm \u2014 preclinical, supports proceeding to trials, nothing more<\/td><\/tr>\n <\/tbody>\n <\/table>\n\n Reading that table honestly: for bone<\/strong>, the two independent 2-year RCTs (437 women combined) say creatine does not raise bone mineral density \u2014 at most it preserves some geometry of the femoral neck when combined with training (Chilibeck) and does nothing without training (S\u00e3o Paulo). For muscle<\/strong>, the effect in women is real but small (+0.37 kg pooled lean mass) and appears to require training. For mood and brain<\/strong>, women are where creatine\u2019s most interesting clinical signal lives \u2014 plausibly because of the 70\u201380% lower baseline stores \u2014 but the total randomized evidence is a few hundred participants, with the adolescent trial null on symptoms. For pregnancy<\/strong>, human work has only just reached pharmacokinetics; every efficacy claim you may read is extrapolated from spiny-mouse and guinea-pig models.<\/p>\n\n Challenge to the popular beliefs:<\/strong> \u201ccreatine makes women bulky\u201d fails twice \u2014 women\u2019s hormonal milieu limits hypertrophy, and the UNSW sex-disaggregated data showed women\u2019s early scale gain was the fluid<\/em> component with no added muscle growth thereafter. But the mirror-image marketing claim \u2014 creatine as a proven menopause therapy \u2014 also overreaches: the peri-menopause trials are tiny (n=15\u201336), weeks long, and partly non-randomized. Real signal, Tier 3, worth watching, not yet worth prescribing.<\/p>\n<\/section>\n\n<section id=\"men\">\n Men\u2019s health<\/span>\n <h2>Hair, DHT and testosterone: one study built the myth, one finally tested it<\/h2>\n The hair-loss belief traces to exactly one trial: 2009, college rugby players, three weeks, reporting a +56%<\/span> DHT rise after loading. It was never replicated \u2014 twelve subsequent studies on testosterone and its metabolites found no significant hormonal increases. In 2025 the first direct<\/em> test arrived: a 12-week RCT in 45 resistance-trained men (5 g\/day vs maltodextrin placebo) measuring hormones and actual hair-follicle outcomes<\/strong> found no group differences in DHT, DHT-to-testosterone ratio, or any hair-growth parameter \u2014 the authors call it strong evidence against the claim (Lak 2025, JISSN<\/i>).<\/p>\n\n <figure aria-label=\"DHT myth provenance chart\">\n <svg viewBox=\"0 0 940 300\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Provenance of the DHT and hair loss myth versus the 2025 direct test<\/title>\n <text x=\"30\" y=\"30\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">ANATOMY OF A MYTH \u2014 the entire DHT\/hair-loss evidence base<\/text>\n\n \n <rect x=\"40\" y=\"60\" width=\"260\" height=\"160\" fill=\"#A63525\" rx=\"3\"\/>\n <text x=\"170\" y=\"90\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">2009 \u00b7 van der Merwe<\/text>\n <text x=\"170\" y=\"114\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">rugby players \u00b7 3 weeks<\/text>\n <text x=\"170\" y=\"134\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">DHT +56% after loading<\/text>\n <text x=\"170\" y=\"158\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">hair NEVER measured<\/text>\n <text x=\"170\" y=\"182\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#F4DEDA\">never replicated<\/text>\n <text x=\"170\" y=\"206\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"11.5\" fill=\"#FFFFFF\">n = 20 \u00b7 one study<\/text>\n\n \n <rect x=\"340\" y=\"60\" width=\"260\" height=\"160\" fill=\"#3F6B7E\" rx=\"3\"\/>\n <text x=\"470\" y=\"90\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">2009\u20132024 \u00b7 12 studies<\/text>\n <text x=\"470\" y=\"118\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#E4E9EC\">total, free testosterone<\/text>\n <text x=\"470\" y=\"138\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#E4E9EC\">& metabolites examined<\/text>\n <text x=\"470\" y=\"166\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">no significant hormonal<\/text>\n <text x=\"470\" y=\"186\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">increases found<\/text>\n\n \n <rect x=\"640\" y=\"60\" width=\"260\" height=\"160\" fill=\"#093644\" rx=\"3\"\/>\n <text x=\"770\" y=\"90\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"14\" fill=\"#FFFFFF\">2025 \u00b7 Lak \u2014 direct test<\/text>\n <text x=\"770\" y=\"114\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">RCT \u00b7 12 wk \u00b7 n=45 \u00b7 5 g\/d<\/text>\n <text x=\"770\" y=\"138\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">DHT: no difference<\/text>\n <text x=\"770\" y=\"158\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">DHT:T ratio: no difference<\/text>\n <text x=\"770\" y=\"178\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#DCE7EC\">hair-growth parameters:<\/text>\n <text x=\"770\" y=\"198\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"12.5\" fill=\"#FFFFFF\">no difference vs placebo<\/text>\n\n <text x=\"30\" y=\"262\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">Caveat kept honest: the 2025 trial includes ISSN-cluster co-authors \u2014 but it is the only direct hair-follicle evidence either way, and it agrees<\/text>\n <text x=\"30\" y=\"280\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">with twelve independent hormone datasets. Creatine is not androgenic and is not chemically or legally a steroid.<\/text>\n <\/svg>\n <figcaption>Fig. 7 \u2014 One unreplicated n=20 study versus the rest of the literature.<\/b> For men with strong family-history androgenic alopecia the theoretical residual risk cannot be reduced to exactly zero, but no measured pathway supports it. Fertility: creatine is concentrated in testes and sperm; small studies suggest neutral-to-positive effects on sperm energetics \u2014 Tier 3\/4, insufficient for claims.<\/figcaption>\n <\/figure>\n<\/section>\n<section id=\"interactions\">\n Co-ingestion & interactions<\/span>\n <h2>Taking creatine with other nutrients, supplements \u2014 and water<\/h2>\n The direct answer to \u201cwill taking it with other macro\/micronutrients or supplements damage me or be unhealthy?\u201d is: no harmful nutrient\u2013creatine interaction has been documented in the controlled literature.<\/strong> The known interactions all concern uptake and effectiveness<\/em>, not safety. The one practical safety issue is not an interaction at all \u2014 it is product purity: multi-ingredient pre-workouts with unverified formulations are the setting where most real-world adverse-event reports arise, which is why plain third-party-tested monohydrate is the defensible choice.<\/p>\n\n <table class=\"wrapok\">\n <caption>Co-ingestion evidence \u2014 effect on uptake, performance, and safety<\/caption>\n <thead><tr><th>Combined with<\/th><th>What the evidence shows<\/th><th>Safety concern?<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>Carbohydrates<\/strong><\/td><td>Insulin drives the muscle creatine transporter (SLC6A8, PI3K\/Akt pathway, analogous to GLUT4). Classic Green\/Steenge work: large carbohydrate doses (~93 g) raised muscle creatine retention substantially; ~50 g carbohydrate + ~50 g protein reproduced the effect with less sugar. Practically: taking creatine with a normal meal captures most of this; chasing it with ~370 g\/day of sugar during loading (as in the original protocols) is unnecessary and its calorie load is the only \u201charm.\u201d<\/td><td class=\"good\">None \u2014 synergistic for uptake<\/td><\/tr>\n <tr><td>Protein \/ amino acids<\/strong><\/td><td>Protein is insulinotropic; co-ingestion enhances retention roughly additively with carbohydrate. The Lugaresi \u2075\u00b9Cr-EDTA trial specifically tested creatine on top of a high-protein diet<\/em> (\u22651.2 g\/kg\/d) and found no kidney harm by tracer-measured GFR \u2014 the popular \u201cprotein + creatine double-taxes the kidneys\u201d claim fails its direct test.<\/td><td class=\"good\">None, including renally<\/td><\/tr>\n <tr><td>Caffeine \/ coffee<\/strong><\/td><td>The one genuinely debated interaction \u2014 about effectiveness<\/em>, not safety. A 1996 study suggested chronic high-dose caffeine (5 mg\/kg) during creatine loading blunted creatine\u2019s ergogenic effect, possibly via opposing muscle-relaxation effects; pharmacokinetics are unaffected (Vanakoski). The 2022 systematic review (Elosegui, 10 studies): acute caffeine after creatine loading works fine and is often synergistic; chronic simultaneous high-dose co-ingestion showed interference in 2 studies, no interaction in 3, synergy in 1. Ordinary coffee (1\u20133 cups) is far below the doses in question. Some people get GI upset taking both at once.<\/td><td class=\"mid\">No health harm; possible ergogenic blunting at high chronic doses \u2014 unresolved<\/td><\/tr>\n <tr><td>\u03b2-alanine<\/strong><\/td><td>2025 systematic review (7 RCTs, n=263): co-supplementation adds little beyond each supplement alone; inconsistent synergy; no added adverse events.<\/td><td class=\"good\">None<\/td><\/tr>\n <tr><td>Micronutrients (vitamin D, calcium, iron\u2026)<\/strong><\/td><td>No documented adverse interactions. Emerging (weak) evidence that vitamin D status may modulate creatine-transporter expression. Creatine does not deplete or block any vitamin or mineral; conversely it spares<\/em> methionine\/SAMe, glycine and arginine by down-regulating endogenous synthesis.<\/td><td class=\"good\">None documented<\/td><\/tr>\n <tr><td>Medications<\/strong><\/td><td>The real-world flags: chronic NSAIDs, nephrotoxic antibiotics, or diuretics in people with reduced kidney function \u2014 not because creatine injures the kidney, but because these settings need clean renal monitoring, which creatine\u2019s creatinine artifact muddies. SSRI co-use appears safe and is the basis of the depression trials. Anyone on prescription drugs affecting kidneys or fluid balance should tell their physician.<\/td><td class=\"mid\">Monitoring issue, not toxicity<\/td><\/tr>\n <tr><td>Multi-ingredient pre-workouts<\/strong><\/td><td>Where adverse-event reports cluster: unverified doses, proprietary blends, stimulant stacking, contamination. In the 28.4-million-report surveillance analysis, half of \u201ccreatine\u201d reports involved products where creatine wasn\u2019t even a listed ingredient.<\/td><td class=\"bad\">The genuine real-world risk \u2014 use plain tested monohydrate instead<\/td><\/tr>\n <tr><td>Water<\/strong><\/td><td>Creatine is osmotically active and shifts ~0.5\u20131 L into the intracellular compartment during saturation. Controlled studies show no dehydration, no impaired thermoregulation, lower core temperatures in heat, and reduced cramping in athlete cohorts. Thirst-guided normal drinking is sufficient; the \u201cgallon rule\u201d has no evidence base. The only water-related realities: expect 1\u20132 kg scale weight from intracellular water, and take powder dissolved in enough fluid (~250\u2013500 mL) to avoid GI upset from large boluses.<\/td><td class=\"good\">None \u2014 the myth runs backwards<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"dose\">\n Dose, overdose & long exposure<\/span>\n <h2>How much is too much? Less alarming \u2014 and less magical \u2014 than believed<\/h2>\n There is no documented lethal or organ-toxic oral dose of creatine monohydrate in humans; the practical ceiling is gastrointestinal. Above muscle saturation (reached by ~3\u20135 g\/day within 3\u20134 weeks, or 20 g\/day for 5\u20137 days), excess creatine is simply excreted unchanged in urine<\/strong> \u2014 expensive urine, not toxicity. The largest safety dataset ever compiled pooled 685 clinical trials<\/span>: 12,839 participants on creatine (average ~12.5 g\/day, durations to 14 years) versus 13,452 on placebo.<\/p>\n\n <figure aria-label=\"Side effects creatine versus placebo\">\n <svg viewBox=\"0 0 940 340\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" role=\"img\">\n <title>Side-effect prevalence, creatine versus placebo, across 685 trials<\/title>\n <text x=\"30\" y=\"26\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"15\" fill=\"#16232B\">SIDE-EFFECT REPORTING ACROSS 685 TRIALS<\/text>\n <text x=\"30\" y=\"46\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"700\" font-size=\"13\" fill=\"#16232B\">(Kreider 2025 \u2014 dataset = all published RCTs; authorship ISSN-cluster, flagged)<\/text>\n\n \n <line x1=\"120\" y1=\"260\" x2=\"880\" y2=\"260\" stroke=\"#16232B\" stroke-width=\"1.5\"\/>\n\n \n <text x=\"240\" y=\"70\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Studies reporting any side effect<\/text>\n \n <rect x=\"160\" y=\"128\" width=\"70\" height=\"132\" fill=\"#7E8D96\"\/>\n <text x=\"195\" y=\"118\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#4A5B66\">13.2%<\/text>\n <text x=\"195\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">placebo<\/text>\n \n <rect x=\"250\" y=\"123\" width=\"70\" height=\"137\" fill=\"#093644\"\/>\n <text x=\"285\" y=\"113\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#0C3A4D\">13.7%<\/text>\n <text x=\"285\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#0C3A4D\">creatine<\/text>\n <text x=\"240\" y=\"308\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">p = 0.776 \u2014 indistinguishable<\/text>\n\n \n <text x=\"600\" y=\"70\" text-anchor=\"middle\" font-family=\"Archivo,Arial,sans-serif\" font-weight=\"600\" font-size=\"13\" fill=\"#16232B\">Participants reporting side effects<\/text>\n \n <rect x=\"520\" y=\"218\" width=\"70\" height=\"42\" fill=\"#7E8D96\"\/>\n <text x=\"555\" y=\"208\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#4A5B66\">4.21%<\/text>\n <text x=\"555\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">placebo<\/text>\n \n <rect x=\"610\" y=\"214\" width=\"70\" height=\"46\" fill=\"#093644\"\/>\n <text x=\"645\" y=\"204\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12.5\" fill=\"#0C3A4D\">4.60%<\/text>\n <text x=\"645\" y=\"280\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#0C3A4D\">creatine<\/text>\n <text x=\"600\" y=\"308\" text-anchor=\"middle\" font-family=\"IBM Plex Mono,monospace\" font-size=\"12\" fill=\"#4A5B66\">p = 0.828 \u2014 indistinguishable<\/text>\n\n <text x=\"700\" y=\"130\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">2026 dose\u2013response analysis,<\/text>\n <text x=\"700\" y=\"148\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">684 RCTs: no dose- or duration-<\/text>\n <text x=\"700\" y=\"166\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">dependent risk increase; placebo<\/text>\n <text x=\"700\" y=\"184\" font-family=\"IBM Plex Mono,monospace\" font-size=\"11.5\" fill=\"#4A5B66\">groups often reported MORE.<\/text>\n <\/svg>\n <figcaption>Fig. 8 \u2014 \u201cOverdose\u201d in the trial record.<\/b> The one reproducible dose-dependent effect is GI upset at loading-size single boluses (\u226510\u201320 g at once) \u2014 solved by splitting doses or skipping loading entirely. Global adverse-event surveillance: creatine appears in 0.00072% of 28.4 million reports, and in nearly half of those it was not even a listed ingredient. Genuinely unknown territory that keeps this out of Tier-1 blanket status: pre-existing CKD, pregnancy, and >10 g\/day sustained for years unsupervised.<\/figcaption>\n <\/figure>\n\n <table class=\"wrapok\">\n <caption>Dosing protocols \u2014 what the evidence supports<\/caption>\n <thead><tr><th>Protocol<\/th><th>Dose<\/th><th>Time to saturation<\/th><th>Evidence note<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>Maintenance (standard)<\/td><td class=\"tnum\">3\u20135 g\/day (or 0.1 g\/kg\/day)<\/td><td class=\"tnum\">3\u20134 weeks<\/td><td class=\"good\">Same end-state as loading; fewest GI complaints; the default<\/td><\/tr>\n <tr><td>Loading (optional)<\/td><td class=\"tnum\">20 g\/day in 4\u00d75 g, 5\u20137 days<\/td><td class=\"tnum\">~1 week<\/td><td class=\"mid\">Faster only; \u201cmust load\u201d is folklore \u2014 loading is never mandatory<\/td><\/tr>\n <tr><td>Post-menopause muscle protocols<\/td><td class=\"tnum\">0.3 g\/kg\/day (high)<\/td><td class=\"tnum\">\u2014<\/td><td class=\"mid\">Used in Chilibeck-line trials; Tier 2\/3 with training<\/td><\/tr>\n <tr><td>Brain \/ sleep-deprivation rescue<\/td><td class=\"tnum\">single 0.2\u20130.35 g\/kg<\/td><td class=\"tnum\">acute (3\u20137.5 h)<\/td><td class=\"mid\">Two small crossover RCTs; proof of concept, not routine advice<\/td><\/tr>\n <tr><td>Hypertrophy beyond training<\/td><td class=\"tnum\">~10 g\/day (proposed)<\/td><td class=\"tnum\">\u2014<\/td><td class=\"bad\">Suggested by UNSW authors after their 5 g null; untested in a dedicated RCT<\/td><\/tr>\n <tr><td>Form<\/td><td colspan=\"3\">Creatine monohydrate<\/strong> \u2014 the only form with the full evidence base; HCl\/ethyl-ester\/\u201cbuffered\u201d variants show no proven advantage and far less safety data. Third-party-tested products (NSF, Informed Choice, USP) avoid contamination, the main real-world risk.<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"myths\">\n Beliefs on trial<\/span>\n <h2>The misconceptions table \u2014 claim, verdict, evidence<\/h2>\n <table class=\"wrapok\">\n <caption>Popular beliefs versus the 2015\u20132026 record<\/caption>\n <thead><tr><th>Popular belief<\/th><th>Verdict<\/th><th>What the evidence actually shows<\/th><th>Grade<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>\u201cCreatine destroys your kidneys\u201d<\/td><td class=\"bad\">Debunked in healthy users<\/td><td>Creatinine-based eGFR falls as an artifact; tracer-measured GFR (Cr-EDTA) unchanged across 26 RCTs; urea, albuminuria, proteinuria silent. Untested: pre-existing CKD long-term.<\/td><td>META\u00d74<\/span><\/td><\/tr>\n <tr><td>\u201cIt dehydrates you and causes cramps\u201d<\/td><td class=\"bad\">Debunked \u2014 direction reversed<\/td><td>No hydration\/thermoregulation impairment in controlled studies; heat trials show lower core temperature and better fluid retention; cramping reduced in athlete cohorts.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cCreatine is basically a steroid\u201d<\/td><td class=\"bad\">Debunked<\/td><td>Chemically an amino-acid derivative; no androgen-receptor activity; legal in all major sport; works via phosphagen energetics, not hormones.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cIt makes your hair fall out\u201d<\/td><td class=\"bad\">Debunked (one caveat)<\/td><td>One unreplicated 2009 n=20 DHT study vs 12 null hormone studies and a 2025 direct hair-follicle RCT showing no differences in DHT, DHT:T, or hair growth.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cYou must load 20 g\/day to start\u201d<\/td><td class=\"bad\">Debunked<\/td><td>3\u20135 g\/day reaches identical saturation in 3\u20134 weeks; loading only changes speed and raises GI complaints.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201cWomen will get bulky\u201d<\/td><td class=\"bad\">Debunked<\/td><td>Hormonal milieu limits hypertrophy; UNSW sex data show women\u2019s early gain was fluid; long-term changes track training, not supplement.<\/td><td>RCT<\/span><\/td><\/tr>\n <tr><td>\u201c5 g\/day adds extra muscle on top of training\u201d<\/td><td class=\"mid\">Overstated<\/td><td>UNSW wash-in RCT: ~2 kg training gain in both arms, p=0.71. Pooled +1.39 kg FFM across 61 trials is real but water-confounded. Strength\/power benefit stands.<\/td><td>META<\/span><\/td><\/tr>\n <tr><td>\u201cIt damages the liver\u201d<\/td><td class=\"bad\">No signal<\/td><td>Hepatic-marker meta-analyses null; 52-week and adolescent-season data within reference ranges. Existing liver disease: untested, supervise.<\/td><td>META<\/span><\/td><\/tr>\n <tr><td>\u201cGreat for skin \/ anti-aging\u201d<\/td><td class=\"mid\">Commercial, unproven orally<\/td><td>All clinical results are topical, multi-ingredient, Beiersdorf-run, unreplicated. No oral-dose skin evidence.<\/td><td>COM<\/span><\/td><\/tr>\n <tr><td>\u201cEveryone is deficient; it\u2019s a vitamin now\u201d<\/td><td class=\"mid\">Overreach<\/td><td>Insufficiency framing rests on NHANES recall data and one researcher\u2019s proposed DRIs (Tier 4). Real exposed groups: vegans, low-meat elders.<\/td><td>COHORT<\/span><\/td><\/tr>\n <tr><td>\u201cBoosts everyone\u2019s brain\u201d<\/td><td class=\"mid\">Condition-dependent<\/td><td>Small memory\/speed effects concentrated in sleep deprivation, vegetarians, older adults; near-zero in rested young omnivores; no global cognition effect.<\/td><td>META<\/span><\/td><\/tr>\n <tr><td>\u201cMore is better \/ megadosing is dangerous\u201d<\/td><td class=\"mid\">Both wrong<\/td><td>Above saturation, excess is excreted; 685-trial record shows placebo-level side effects at ~12.5 g\/day average; GI upset is the real dose ceiling; >10 g\/day for years unsupervised remains unstudied.<\/td><td>META<\/span><\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"precursors\">\n Adjacent amino acids<\/span>\n <h2>The precursor system and the co-supplement neighbours<\/h2>\n Glycine, arginine and methionine<\/strong> are the three amino acids the body spends to make creatine, and NHANES III (n=29,945) shows precursor availability declines with age \u2014 lowest in adults \u226565, precisely the group with the lowest meat intake and the most muscle to lose. Supplemental creatine measurably spares<\/em> this pathway: it down-regulates AGAT, freeing arginine and glycine for other roles and relieving the ~40% SAMe methylation burden \u2014 a mechanistic argument for supplementation in low-protein contexts that is stronger than most marketing claims, though still Tier 3.<\/p>\n The commonly bundled neighbours, briefly and honestly: guanidinoacetate (GAA)<\/strong> \u2014 creatine\u2019s direct precursor, effective at raising creatine in animal feed science, but raises homocysteine and is not an approved human supplement. \u03b2-alanine<\/strong> \u2014 a genuinely evidence-backed buffer (carnosine) for 1\u20134-minute efforts; a 2025 systematic review of 7 RCTs (n=263) found creatine + \u03b2-alanine co-supplementation adds little beyond each alone, with inconsistent synergy. Taurine and carnitine<\/strong> \u2014 fellow \u201ccarninutrients\u201d absent from plants; neither substitutes for creatine\u2019s phosphagen role. The pattern across all of them: the omnivorous diet quietly supplies a package of nitrogen compounds that vegan diets must synthesise or supplement, and creatine is simply the best-studied member.<\/p>\n<\/section>\n\n<section id=\"tiers\">\n Summary<\/span>\n <h2>Final tier placements<\/h2>\n <table class=\"wrapok\">\n <caption>Every major claim, placed<\/caption>\n <thead><tr><th>Tier<\/th><th>Claims placed here<\/th><\/tr><\/thead>\n <tbody>\n <tr><td class=\"tnum\" style=\"background:#093644;color:#fff;font-weight:700\">TIER 1 HIGH<\/td><td>Creatinine-rise-without-injury artifact \u00b7 safety of 3\u20135 g\/day in healthy adults (685-trial record) \u00b7 repeated-sprint strength\/power ergogenics \u00b7 no dehydration or cramping causation \u00b7 monohydrate as the reference form.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#14556E;color:#fff;font-weight:700\">TIER 2 MODERATE<\/td><td>Pooled lean-mass gain ~1.0\u20131.4 kg (water-confounded; UNSW dissent noted) \u00b7 cognition under metabolic stress (sleep loss, vegetarians, elders) \u00b7 women\u2019s strength gains with resistance training \u00b7 post-menopausal muscle at high dose with training.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#3F6B7E;color:#fff;font-weight:700\">TIER 3 EMERGING<\/td><td>Menopause bone\/sleep signals \u00b7 depression augmentation (esp. women) \u00b7 single-dose brain rescue \u00b7 dietary-insufficiency epidemiology \u00b7 precursor-sparing rationale in low-protein diets \u00b7 fertility energetics.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#96600B;color:#fff;font-weight:700\">TIER 4 CONTESTED<\/td><td>Proposed DRIs (400\/240 mg AI) \u00b7 extra hypertrophy at 5 g\/day \u00b7 ~10 g\/day hypertrophy hypothesis \u00b7 topical skin claims (commercial) \u00b7 use in pre-existing CKD or liver disease \u00b7 perimenopause protocols.<\/td><\/tr>\n <tr><td class=\"tnum\" style=\"background:#A63525;color:#fff;font-weight:700\">TIER 5 DEBUNKED<\/td><td>Kidney destruction in healthy users \u00b7 dehydration\/cramping \u00b7 steroid equivalence \u00b7 hair loss \u00b7 mandatory loading \u00b7 \u201cwomen get bulky\u201d \u00b7 fat-gain claims.<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"plain-summary\">\n The questions, answered plainly<\/span>\n <h2>Summary: the popular beliefs versus this evidence base<\/h2>\n\n <h3>Does long-term intake damage the kidneys?<\/h3>\n Not in healthy kidneys, on every creatinine-independent measurement ever taken. Five years of observational use (Poortmans), two years of continuous placebo-controlled use (Bender), tracer-measured GFR trials including on high-protein diets, in diabetics, and in postmenopausal women \u2014 all clean. What long-term intake does do is permanently raise serum creatinine while you take it, which can be misread<\/em> as kidney damage in routine blood work; the harm there is misdiagnosis, not nephrotoxicity. The honest boundary: no long-term RCTs exist in people who already have chronic kidney disease, so pre-existing CKD, a single kidney, or nephrotoxic medication use means physician supervision, not self-experimentation. The popular belief \u201ccreatine destroys kidneys\u201d is debunked for healthy users; the marketing belief \u201cproven safe for everyone forever\u201d overreaches into the untested CKD gap.<\/p>\n\n <h3>Is it good for women\u2019s health?<\/h3>\n Selectively \u2014 and less broadly than the current wave of marketing implies. Best-supported: strength and performance gains alongside resistance training, and the mood\/brain-energetics signal, where the independent Lyoo RCT (52 women, creatine + SSRI) showed one of the largest augmentation effects in the file and imaging trials show the mechanism engaging. Genuinely disappointing: bone \u2014 the two independent 2-year RCTs totalling 437 postmenopausal women found no bone-mineral-density benefit, and the S\u00e3o Paulo trial found no lean-mass or function benefit without training either. Genuinely unknown: perimenopause (first tiny trials only appeared in 2025) and pregnancy (human research reached pharmacokinetics in 2025; all efficacy claims are still animal-model extrapolation \u2014 do not supplement in pregnancy outside a trial). Female physiology (70\u201380% lower stores) makes women plausible high-responders, and female-specific safety data are clean (951 women, no serious adverse events), but \u201cevery woman should take creatine\u201d is a slogan, not a finding.<\/p>\n\n <h3>What are the side effects \u2014 men and women, short and long term?<\/h3>\n Across 685 trials and ~26,000 participants, side-effect rates are statistically indistinguishable from placebo (13.7% vs 13.2% of studies; 4.60% vs 4.21% of participants). The reproducible effects: 1\u20132 kg of intracellular water weight in the first weeks (larger and quicker in women per the UNSW wash-in data \u2014 fluid, not fat or muscle), and dose-dependent GI upset when large boluses (\u226510\u201320 g at once) are taken, solved by splitting doses. Sex-specific fears tested and failed: hair loss\/DHT in men (one unreplicated n=20 study vs a direct 2025 follicle RCT showing nothing), \u201cbulkiness\u201d in women (hormonal ceiling plus fluid misread). Long-term (to 2\u20135 years at 3\u201310 g\/day): no organ-damage signal in kidney, liver, blood, or cardiometabolic panels; the permanent lab artifact on creatinine is the only lasting change. The genuine long-term unknown is unsupervised decades-scale megadosing, which no one has studied.<\/p>\n\n <h3>Will taking it with other nutrients or supplements be damaging or unhealthy?<\/h3>\n No documented harmful nutrient interaction exists. Carbohydrate and protein co-ingestion help<\/em> (insulin-mediated uptake); the high-protein-plus-creatine kidney scare failed its direct tracer-GFR test; \u03b2-alanine coexists neutrally; micronutrients show no adverse interplay. The only substantive debate is caffeine \u2014 a possible blunting of creatine\u2019s performance<\/em> effect under chronic high-dose co-ingestion, unresolved since 1996 and irrelevant to health; normal coffee drinking is fine. The one real-world hazard is not an interaction: it is unverified multi-ingredient products, where most adverse-event reports originate. Plain, third-party-tested creatine monohydrate avoids it.<\/p>\n\n <h3>How much water should be taken with it?<\/h3>\n Normal, thirst-guided intake. The dehydration\/cramping belief is not just unsupported \u2014 controlled studies point the other way (better fluid retention, lower core temperature in heat, fewer cramps in athlete cohorts). Dissolve doses in roughly a glass (250\u2013500 mL) to protect the gut, expect the scale to rise 1\u20132 kg from water stored inside<\/em> muscle cells, and ignore the gallon rule.<\/p>\n\n <div class=\"callout\">\n Boundaries of this summary<\/span>\n These answers apply to healthy adults using plain creatine monohydrate at 3\u201310 g\/day. They do not extend to: pregnancy or breastfeeding (PK data only), anyone under 18 (limited data), pre-existing kidney or liver disease (untested long term), or unverified multi-ingredient products. All figures require verification against primary sources before clinical or published use.<\/p>\n <\/div>\n<\/section>\n\n\n<section id=\"study-table\">\n Study metadata<\/span>\n <h2>The reference base at a glance \u2014 all 73 sources, tabulated<\/h2>\n \n How to read this table: \"\u2014\" = not stated in the citation or in the document text \u00b7 \"n\/a\" = not applicable\n (reviews, meta-analyses, consensus documents and dataset analyses have no single intervention period) \u00b7\n a \"~\" before a country = inferred from the lead author's affiliation, not stated in the source \u00b7\n author counts reflect names listed in the citation, and \"+\" means \"et al.\" (more authors than listed) \u00b7\n calendar dates of trial conduct are almost never stated in citations, so the from\u2013to column is filled only where a source states it.\n Consistent with the standing caveat, every field requires verification against the primary source before clinical or published use.<\/p>\n <table class=\"wrapok\">\n <caption>Study-metadata table \u2014 one row per reference, in reference-list order<\/caption>\n <thead><tr><th>Reference<\/th><th>Research period (duration)<\/th><th>Participants (n)<\/th><th>Researchers (authors listed)<\/th><th>Year published<\/th><th>Study years (from\u2013to)<\/th><th>Country<\/th><th>Type<\/th><th>Section<\/th><\/tr><\/thead>\n <tbody>\n<tr><td class=\"tnum\">Brosnan 2016<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>2<\/td><td>2016<\/td><td>\u2014<\/td><td>~Canada<\/td><td>INDEPENDENT<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2026 (DRI proposal)<\/strong><\/td><td>n\/a (DRI proposal)<\/td><td>\u2014<\/td><td>1<\/td><td>2026<\/td><td>\u2014<\/td><td>~Norway<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Nedeljkovic 2025<\/strong><\/td><td>n\/a (dietary-exposure analysis)<\/td><td>\u2014<\/td><td>2<\/td><td>2025<\/td><td>\u2014<\/td><td>~Norway\/Serbia<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2021<\/strong><\/td><td>n\/a (dietary survey)<\/td><td>4,291 (children)<\/td><td>1<\/td><td>2021<\/td><td>\u2014<\/td><td>~Serbia<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2026 (NHANES mortality)<\/strong><\/td><td>n\/a (linked-mortality cohort)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2026<\/td><td>NHANES (years not stated)<\/td><td>USA (data)<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Candow 2025<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~Canada<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Requirement & synthesis<\/td><\/tr>\n<tr><td class=\"tnum\">Desai 2025 (UNSW)<\/strong><\/td><td>7 d wash-in + 12 wk training<\/td><td>63<\/td><td>7<\/td><td>2025<\/td><td>\u2014<\/td><td>Australia<\/td><td>INDEPENDENT \u2014 design\/lead<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Barranco-Gil 2024<\/strong><\/td><td>6 d loading (20 g\/d)<\/td><td>23<\/td><td>1+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>Spain<\/td><td>INDEPENDENT<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Ashtary-Larky 2025 (61 trials)<\/strong><\/td><td>n\/a (meta-analysis, 61 trials)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~multinational<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Burke 2023<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2023<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Backx 2017<\/strong><\/td><td>leg-immobilization RCT<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2017<\/td><td>\u2014<\/td><td>~Netherlands<\/td><td>INDEPENDENT<\/span><\/td><td>Muscle & strength<\/td><\/tr>\n<tr><td class=\"tnum\">Int Urol Nephrol 2026<\/strong><\/td><td>n\/a (meta-analysis, 26 RCTs)<\/td><td>1,036<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">KabiriNaeini 2025<\/strong><\/td><td>n\/a (meta-analysis, 21 studies)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~Iran<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Tsiaras 2026<\/strong><\/td><td>n\/a (meta-analysis, 19 RCTs)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">de Souza e Silva 2019<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2019<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Renal Failure 2024 (MR)<\/strong><\/td><td>n\/a (Mendelian randomization)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2024<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Gualano 2011<\/strong><\/td><td>12 wk<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2011<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Poortmans & Francaux 1999<\/strong><\/td><td>10 mo\u20135 yr of use<\/td><td>\u2014<\/td><td>2<\/td><td>1999<\/td><td>\u2014<\/td><td>~Belgium<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Kreider 2003<\/strong><\/td><td>21 mo<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2003<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Gualano 2008<\/strong><\/td><td>12 wk<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2008<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Lugaresi 2013<\/strong><\/td><td>12 wk<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2013<\/td><td>\u2014<\/td><td>Brazil<\/td><td>INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Neves 2011<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2011<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Bender 2008<\/strong><\/td><td>2 yr<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2008<\/td><td>\u2014<\/td><td>~Germany<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Gualano 2010<\/strong><\/td><td>short-term, high dose<\/td><td>1 (single kidney)<\/td><td>3+ (et al.)<\/td><td>2010<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Longobardi 2023<\/strong><\/td><td>n\/a (narrative review)<\/td><td>\u2014<\/td><td>4<\/td><td>2023<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Pritchard & Kalra 1998<\/strong><\/td><td>n\/a (case letter)<\/td><td>1<\/td><td>2<\/td><td>1998<\/td><td>\u2014<\/td><td>~UK<\/td><td>INDEPENDENT \u2014 n=1, pre-existing kidney disease<\/span><\/td><td>Kidney<\/td><\/tr>\n<tr><td class=\"tnum\">Kreider 2025 (685 trials)<\/strong><\/td><td>n\/a (685-trial dataset)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Sports 2026 (684 RCTs)<\/strong><\/td><td>n\/a (dose\u2013response, 684 RCTs)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Longobardi 2025<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>4<\/td><td>2025<\/td><td>\u2014<\/td><td>~Brazil<\/td><td>INDEPENDENT \u2014 academic; some cluster overlap<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Alizadeh 2022<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2022<\/td><td>\u2014<\/td><td>~Iran<\/td><td>INDEPENDENT<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Kashi 2024<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Cureus 2026 (adolescents)<\/strong><\/td><td>n\/a (systematic review)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Kreider 2017 (position stand)<\/strong><\/td><td>n\/a (consensus)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2017<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Safety & liver<\/td><\/tr>\n<tr><td class=\"tnum\">Gordji-Nejad 2024<\/strong><\/td><td>single dose \u00b7 21 h sleep deprivation<\/td><td>15<\/td><td>2+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>Germany (J\u00fclich)<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Nutrients 2026 (0.2 g\/kg)<\/strong><\/td><td>single dose<\/td><td>29<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Xu 2024<\/strong><\/td><td>n\/a (meta-analysis, 16 RCTs)<\/td><td>492<\/td><td>4<\/td><td>2024<\/td><td>\u2014<\/td><td>~China<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Rae 2003<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2003<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Brain & cognition<\/td><\/tr>\n<tr><td class=\"tnum\">Smith-Ryan 2025<\/strong><\/td><td>n\/a (lifespan review)<\/td><td>\u2014<\/td><td>6<\/td><td>2025<\/td><td>\u2014<\/td><td>~USA\/Australia<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Smith-Ryan 2021<\/strong><\/td><td>n\/a (lifespan review)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2021<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">de Guingand 2020<\/strong><\/td><td>n\/a (meta-analysis, 29 studies)<\/td><td>951<\/td><td>5<\/td><td>2020<\/td><td>\u2014<\/td><td>Australia (Monash)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Gordon 2023<\/strong><\/td><td>loading, both cycle phases (crossover)<\/td><td>39<\/td><td>1+ (et al.)<\/td><td>2023<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Hall 2025<\/strong><\/td><td>quasi-experimental<\/td><td>15<\/td><td>4<\/td><td>2025<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">CONCRET-MENOPA 2025<\/strong><\/td><td>8 wk<\/td><td>36<\/td><td>not listed<\/td><td>2025<\/td><td>\u2014<\/td><td>\u2014<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Ostojic 2024 (NHANES)<\/strong><\/td><td>n\/a (NHANES survey)<\/td><td>\u2014<\/td><td>4<\/td><td>2024<\/td><td>2017\u20132020 (NHANES)<\/td><td>USA (data)<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Ellery 2016<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>3<\/td><td>2016<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Chilibeck 2015<\/strong><\/td><td>12 mo<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2015<\/td><td>\u2014<\/td><td>~Canada<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Chilibeck 2023<\/strong><\/td><td>2 yr<\/td><td>237<\/td><td>3+ (et al.)<\/td><td>2023<\/td><td>\u2014<\/td><td>Canada (Saskatchewan\/Regina)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Sales 2020<\/strong><\/td><td>2 yr<\/td><td>200 (osteopenia)<\/td><td>2+ (et al.)<\/td><td>2020<\/td><td>\u2014<\/td><td>Brazil (S\u00e3o Paulo)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Postmenopausal meta 2025<\/strong><\/td><td>n\/a (meta-analysis)<\/td><td>\u2014<\/td><td>not listed<\/td><td>2025<\/td><td>searches to Aug 2025<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Lyoo 2012<\/strong><\/td><td>8 wk<\/td><td>52<\/td><td>3+ (et al.)<\/td><td>2012<\/td><td>\u2014<\/td><td>~South Korea<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Yoon 2016<\/strong><\/td><td>8 wk<\/td><td>34 (imaging arm)<\/td><td>2+ (et al.)<\/td><td>2016<\/td><td>\u2014<\/td><td>~South Korea<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Kondo 2016<\/strong><\/td><td>8 wk, dose-ranging 2\/4\/10 g\/d<\/td><td>33<\/td><td>2+ (et al.)<\/td><td>2016<\/td><td>\u2014<\/td><td>USA (NIMH-funded)<\/td><td>INDEPENDENT \u2014 NIMH<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Fares 2026<\/strong><\/td><td>n\/a (systematic review)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2026<\/td><td>\u2014<\/td><td>~Canada<\/td><td>INDEPENDENT \u2014 cluster co-authors noted<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Dickinson 2016<\/strong><\/td><td>n\/a (retrospective cohort)<\/td><td>287<\/td><td>3+ (et al.)<\/td><td>2016<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">de Guingand 2024 (CPO)<\/strong><\/td><td>pregnancy (prospective cohort)<\/td><td>282<\/td><td>6<\/td><td>2024<\/td><td>\u2014<\/td><td>Australia (Hudson\/Monash)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Muccini 2021<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2021<\/td><td>\u2014<\/td><td>~Australia<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Naidu 2025<\/strong><\/td><td>dose-escalation PK (pregnancy)<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>Australia (Monash)<\/td><td>INDEPENDENT<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Freeman 2025<\/strong><\/td><td>full-term pregnancy (animal model)<\/td><td>n\/a (guinea pigs)<\/td><td>4<\/td><td>2025<\/td><td>\u2014<\/td><td>~Australia\/NZ<\/td><td>INDEPENDENT \u2014 preclinical<\/span><\/td><td>Women's health<\/td><\/tr>\n<tr><td class=\"tnum\">Lak 2025<\/strong><\/td><td>12 wk<\/td><td>45<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~Iran + intl.<\/td><td>ISSN-CLUSTER \u2014 only direct hair evidence; concordant with 12 independent hormone datasets<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">van der Merwe 2009<\/strong><\/td><td>3 wk<\/td><td>20<\/td><td>3<\/td><td>2009<\/td><td>\u2014<\/td><td>~South Africa<\/td><td>INDEPENDENT \u2014 single unreplicated origin of the myth<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">Antonio 2021<\/strong><\/td><td>n\/a (consensus)<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>2021<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER \u2014 consensus document<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">Antonio 2024 (Part II)<\/strong><\/td><td>n\/a (consensus)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2024<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER \u2014 consensus document<\/span><\/td><td>Men's health & hair<\/td><\/tr>\n<tr><td class=\"tnum\">Peirano 2011<\/strong><\/td><td>6 wk<\/td><td>43 (men)<\/td><td>2+ (et al.)<\/td><td>2011<\/td><td>\u2014<\/td><td>Germany<\/td><td>COMMERCIAL \u2014 Beiersdorf<\/span><\/td><td>Skin<\/td><\/tr>\n<tr><td class=\"tnum\">Lenz 2005<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2005<\/td><td>\u2014<\/td><td>Germany<\/td><td>COMMERCIAL \u2014 Beiersdorf<\/span><\/td><td>Skin<\/td><\/tr>\n<tr><td class=\"tnum\">Knott 2008<\/strong><\/td><td>\u2014<\/td><td>\u2014<\/td><td>2+ (et al.)<\/td><td>2008<\/td><td>\u2014<\/td><td>Germany<\/td><td>COMMERCIAL \u2014 Beiersdorf<\/span><\/td><td>Skin<\/td><\/tr>\n<tr><td class=\"tnum\">Elosegui 2022<\/strong><\/td><td>n\/a (systematic review, 10 studies)<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>2022<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Trexler & Smith-Ryan 2015<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>2<\/td><td>2015<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Vandenberghe 1996<\/strong><\/td><td>loading period<\/td><td>\u2014<\/td><td>1+ (et al.)<\/td><td>1996<\/td><td>\u2014<\/td><td>~Belgium<\/td><td>INDEPENDENT \u2014 origin of the caffeine debate, contested since<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Green 1996<\/strong><\/td><td>acute\/loading<\/td><td>\u2014<\/td><td>3+ (et al.)<\/td><td>1996<\/td><td>\u2014<\/td><td>~UK<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Steenge 2000<\/strong><\/td><td>acute<\/td><td>\u2014<\/td><td>3<\/td><td>2000<\/td><td>\u2014<\/td><td>~UK<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Sci Rep 2026 (4-group RCT)<\/strong><\/td><td>\u2014<\/td><td>60<\/td><td>not listed<\/td><td>2026<\/td><td>\u2014<\/td><td>\u2014<\/td><td>INDEPENDENT<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Stecker 2019<\/strong><\/td><td>n\/a (review)<\/td><td>\u2014<\/td><td>5<\/td><td>2019<\/td><td>\u2014<\/td><td>~USA<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Co-ingestion & interactions<\/td><\/tr>\n<tr><td class=\"tnum\">Ashtary-Larky 2025 (\u03b2-alanine)<\/strong><\/td><td>n\/a (systematic review, 7 RCTs)<\/td><td>263<\/td><td>3+ (et al.)<\/td><td>2025<\/td><td>\u2014<\/td><td>~multinational<\/td><td>ISSN-CLUSTER<\/span><\/td><td>Adjacent co-supplements<\/td><\/tr>\n <\/tbody>\n <\/table>\n<\/section>\n\n<section id=\"references\" class=\"refs\">\n Sources<\/span>\n <h2>References \u2014 grouped, with independence tags<\/h2>\n INDEPENDENT<\/span> no disclosed supplement-industry ties ISSN-CLUSTER<\/span> rigorous but industry-adjacent authorship\/venue COMMERCIAL<\/span> manufacturer-run<\/p>\n\n <h3>Requirement, synthesis & precursor amino acids<\/h3>\n <ol>\n <li>Brosnan JT, Brosnan ME. The role of dietary creatine. Amino Acids<\/i> 2016;48:1785\u20131791. doi:10.1007\/s00726-016-2188-1<\/span> INDEPENDENT<\/span><\/li>\n <li>Ostojic SM. Establishing Dietary Reference Intakes for creatine in adults. Nutrition Reviews<\/i> 2026;nuag009. doi:10.1093\/nutrit\/nuag009<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Nedeljkovic D, Ostojic SM. Dietary exposure to creatine-precursor amino acids in the general population. Amino Acids<\/i> 2025;57:29. doi:10.1007\/s00726-025-03460-7<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ostojic SM. Creatine as a food supplement for the general population. J Functional Foods<\/i> 2021;83:104568. doi:10.1016\/j.jff.2021.104568<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ostojic SM et al. Dietary creatine intake and all-cause mortality: NHANES linked-mortality analysis. Appl Physiol Nutr Metab<\/i> 2026. doi:10.1139\/apnm-2025-0001<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Candow DG, Ostojic SM, Chilibeck PD, et al. Creatine monohydrate supplementation for older adults and clinical populations. JISSN<\/i> 2025;22(sup1):2534130. doi:10.1080\/15502783.2025.2534130<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n\n <h3>Muscle & strength \u2014 including dissenting independents<\/h3>\n <ol>\n <li>Desai I, Pandit A, Smith-Ryan AE, Simar D, Candow DG, Kaakoush NO, Hagstrom AD. The effect of creatine supplementation on lean body mass with and without resistance training. Nutrients<\/i> 2025;17(6):1081. doi:10.3390\/nu17061081<\/span> INDEPENDENT (design\/lead)<\/span><\/li>\n <li>Barranco-Gil D, et al. High-dose short-term creatine supplementation without beneficial effects in professional cyclists: RCT. JISSN<\/i> 2024;21:2340574. doi:10.1080\/15502783.2024.2340574<\/span> INDEPENDENT<\/span><\/li>\n <li>Ashtary-Larky D, et al. Creatine supplementation and resistance training: novice vs experienced lifters \u2014 systematic review and dose\u2013response meta-analysis (61 trials). JISSN<\/i> 2025;22(sup1):2586523. doi:10.1080\/15502783.2025.2586523<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Burke R, Pi\u00f1ero A, Coleman M, et al. Creatine + resistance training and regional hypertrophy: systematic review with meta-analysis. Nutrients<\/i> 2023;15(9):2116. doi:10.3390\/nu15092116<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Backx EMP, et al. Creatine loading does not preserve muscle mass or strength during leg immobilization: RCT. Sports Med<\/i> 2017;47:1661\u20131671. doi:10.1007\/s40279-016-0670-2<\/span> INDEPENDENT<\/span><\/li>\n <\/ol>\n\n <h3>Kidney<\/h3>\n <ol>\n <li>[Anon. authors] Impact of creatine supplementation on kidney health: systematic review and meta-analysis (26 RCTs, Cr-EDTA subanalysis). Int Urol Nephrol<\/i> 2026. doi:10.1007\/s11255-026-05287-x<\/span> INDEPENDENT<\/span><\/li>\n <li>KabiriNaeini E, Eskandari M, Mortazavi M, et al. Effect of creatine supplementation on kidney function: systematic review and meta-analysis. BMC Nephrology<\/i> 2025;26:622. doi:10.1186\/s12882-025-04558-6<\/span> INDEPENDENT<\/span><\/li>\n <li>Tsiaras A, et al. The effect of creatine supplementation on kidney function: systematic review and meta-analysis of RCTs. J Renal Nutrition<\/i> 2026. doi:10.1016\/S1051-2276(26)00082-8<\/span> INDEPENDENT<\/span><\/li>\n <li>de Souza e Silva A, et al. Effects of creatine supplementation on renal function: systematic review and meta-analysis. J Renal Nutrition<\/i> 2019;29(6):480\u2013489. doi:10.1053\/j.jrn.2019.05.004<\/span> INDEPENDENT<\/span><\/li>\n <li>Exploring creatine supplementation and renal function: Mendelian randomization analysis. Renal Failure<\/i> 2024;46(2):2364762. doi:10.1080\/0886022X.2024.2364762<\/span> INDEPENDENT<\/span><\/li>\n <li>Gualano B, et al. Creatine supplementation does not impair kidney function in type 2 diabetic patients: RCT (\u2075\u00b9Cr-EDTA). Eur J Appl Physiol<\/i> 2011;111:749\u2013756. doi:10.1007\/s00421-010-1676-3<\/span> INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/li>\n <li>Poortmans JR, Francaux M. Long-term oral creatine supplementation does not impair renal function in healthy athletes (10 mo\u20135 yr). Med Sci Sports Exerc<\/i> 1999;31:1108\u20131110. doi:10.1097\/00005768-199908000-00005<\/span> INDEPENDENT<\/span><\/li>\n <li>Kreider RB, et al. Long-term creatine supplementation does not significantly affect clinical markers of health in athletes (21 mo). Mol Cell Biochem<\/i> 2003;244:95\u2013104. doi:10.1023\/A:1022469320296<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Gualano B, Ugrinowitsch C, et al. Effects of creatine supplementation on renal function: RCT with cystatin C. Eur J Appl Physiol<\/i> 2008;103:33\u201340. doi:10.1007\/s00421-007-0669-3<\/span> INDEPENDENT<\/span><\/li>\n <li>Lugaresi R, Leme M, de Salles Painelli V, et al. Does long-term creatine supplementation impair kidney function in resistance-trained individuals consuming a high-protein diet? (\u2075\u00b9Cr-EDTA). JISSN<\/i> 2013;10:26. doi:10.1186\/1550-2783-10-26<\/span> INDEPENDENT<\/span><\/li>\n <li>Neves M Jr, Gualano B, et al. Effect of creatine supplementation on measured glomerular filtration rate in postmenopausal women. Appl Physiol Nutr Metab<\/i> 2011;36:419\u2013422. doi:10.1139\/h11-014<\/span> INDEPENDENT<\/span><\/li>\n <li>Bender A, et al. Long-term creatine supplementation is safe in aged patients with Parkinson disease (2-yr, renal markers incl. cystatin C). Nutr Res<\/i> 2008;28:172\u2013178. doi:10.1016\/j.nutres.2008.01.001<\/span> INDEPENDENT<\/span><\/li>\n <li>Gualano B, Ferreira DC, Sapienza MT, et al. Effect of short-term high-dose creatine supplementation on measured GFR in a young man with a single kidney. Am J Kidney Dis<\/i> 2010;55(3):e7\u2013e9. doi:10.1053\/j.ajkd.2009.10.053<\/span> INDEPENDENT<\/span><\/li>\n <li>Longobardi I, Gualano B, Seguro AC, Roschel H. Is it time for a requiem for creatine supplementation-induced kidney failure? A narrative review. Nutrients<\/i> 2023;15:1466. doi:10.3390\/nu15061466<\/span> INDEPENDENT<\/span><\/li>\n <li>Pritchard NR, Kalra PA. Renal dysfunction accompanying oral creatine supplements (case letter \u2014 provenance of the scare). Lancet<\/i> 1998;351:1252\u20131253. doi:10.1016\/S0140-6736(05)79319-3<\/span> INDEPENDENT \u2014 n=1, pre-existing kidney disease<\/span><\/li>\n <\/ol>\n\n <h3>Safety, liver & adverse events<\/h3>\n <ol>\n <li>Kreider RB, et al. Safety of creatine supplementation: prevalence of reported side effects in clinical trials and adverse event reports (685 trials). JISSN<\/i> 2025;22:2488937. doi:10.1080\/15502783.2025.2488937<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Creatine supplementation dose and duration are not associated with increased side effects: study-level dose\u2013response analysis of 684 RCTs. Sports<\/i> 2026;14(4):137. doi:10.3390\/sports14040137<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Longobardi I, Solis MY, Roschel H, Gualano B. A short review of the most common safety concerns regarding creatine ingestion. Frontiers in Nutrition<\/i> 2025;12:1682746. doi:10.3389\/fnut.2025.1682746<\/span> INDEPENDENT (academic; some cluster overlap)<\/span><\/li>\n <li>Alizadeh S, et al. Effects of creatine supplementation on hepatic markers: systematic review and meta-analysis. Sports Med Open<\/i> 2022;8:126. doi:10.1186\/s40798-022-00518-w<\/span> INDEPENDENT<\/span><\/li>\n <li>Kashi S, et al. Effects of creatine supplementation on renal and hepatic function: systematic review and meta-analysis. Nutr Res Rev<\/i> 2024;37:E30. doi:10.1017\/S095442242400003X<\/span> INDEPENDENT<\/span><\/li>\n <li>Evaluating the safety of creatine monohydrate in adolescents: systematic review of renal, hepatic and cardiometabolic outcomes. Cureus<\/i> 2026. INDEPENDENT<\/span><\/li>\n <li>Kreider RB, et al. ISSN position stand: safety and efficacy of creatine supplementation. JISSN<\/i> 2017;14:18. doi:10.1186\/s12970-017-0173-z<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n\n <h3>Brain, cognition & mood<\/h3>\n <ol>\n <li>Gordji-Nejad A, Matusch A, et al. Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation. Scientific Reports<\/i> 2024;14:4937. doi:10.1038\/s41598-024-54249-9<\/span> INDEPENDENT<\/span><\/li>\n <li>Single-dose creatine (0.2 g\/kg) reduces sleep-deprivation-induced deterioration in cognitive performance. Nutrients<\/i> 2026;18(8):1192. doi:10.3390\/nu18081192<\/span> INDEPENDENT<\/span><\/li>\n <li>Xu C, Bi S, Zhang W, Luo L. Effects of creatine supplementation on cognitive function in adults: systematic review and meta-analysis (16 RCTs). Frontiers in Nutrition<\/i> 2024;11:1424972. doi:10.3389\/fnut.2024.1424972<\/span> INDEPENDENT<\/span><\/li>\n <li>Rae C, et al. Oral creatine monohydrate supplementation improves brain performance (vegetarians). Proc Biol Sci<\/i> 2003;270:2147\u20132150. doi:10.1098\/rspb.2003.2492<\/span> INDEPENDENT<\/span><\/li>\n <\/ol>\n\n <h3>Women\u2019s health<\/h3>\n <ol>\n <li>Smith-Ryan AE, DelBiondo GM, Brown AF, Kleiner SM, Tran NT, Ellery SJ. Creatine in women\u2019s health: bridging the gap from menstruation through pregnancy to menopause. JISSN<\/i> 2025;22:2502094. doi:10.1080\/15502783.2025.2502094<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Smith-Ryan AE, et al. Creatine supplementation in women\u2019s health: a lifespan perspective. Nutrients<\/i> 2021;13(3):877. doi:10.3390\/nu13030877<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>de Guingand DL, Palmer KR, Snow RJ, Davies-Tuck ML, Ellery SJ. Risk of adverse outcomes in females taking oral creatine monohydrate: systematic review and meta-analysis. Nutrients<\/i> 2020;12(6):1780. doi:10.3390\/nu12061780<\/span> INDEPENDENT<\/span><\/li>\n <li>Gordon AN, et al. Creatine monohydrate loading and exercise recovery in active women throughout the menstrual cycle. Nutrients<\/i> 2023;15(16):3567. doi:10.3390\/nu15163567<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Hall L, Klassen S, Holbein J, Waters J. Impact of creatine supplementation on menopausal women\u2019s body composition, cognition, estrogen, strength, and sleep. JISSN<\/i> 2025;22:2533673. doi:10.1080\/15502783.2025.2533673<\/span> INDEPENDENT<\/span><\/li>\n <li>CONCRET-MENOPA: 8-week creatine HCl \/ ethyl ester RCT in perimenopausal and menopausal women. J Am Nutr Assoc<\/i> 2025;45(3):199\u2013210. doi:10.1080\/27697061.2025.2551184<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ostojic SM, Stea TH, Ellery SJ, Smith-Ryan AE. Dietary creatine intake and female reproductive health: NHANES 2017\u20132020. Food Sci Nutr<\/i> 2024;12:4135. doi:10.1002\/fsn3.4135<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Ellery SJ, Walker DW, Dickinson H. Creatine for women: creatine and the reproductive cycle. Amino Acids<\/i> 2016;48:1807\u20131817. doi:10.1007\/s00726-016-2199-y<\/span> INDEPENDENT<\/span><\/li>\n <li>Chilibeck PD, et al. Effects of creatine and resistance training on bone health in postmenopausal women (12-mo RCT). Med Sci Sports Exerc<\/i> 2015;47:1587\u20131595. doi:10.1249\/MSS.0000000000000571<\/span> INDEPENDENT<\/span><\/li>\n <li>Chilibeck PD, Candow DG, Gordon JJ, et al. A 2-yr randomized controlled trial on creatine supplementation during exercise for postmenopausal bone health (n=237). Med Sci Sports Exerc<\/i> 2023;55:1750\u20131760. doi:10.1249\/MSS.0000000000003202<\/span> INDEPENDENT \u2014 Univ. Saskatchewan\/Regina<\/span><\/li>\n <li>Sales LP, Pinto AJ, et al. (Gualano group). Creatine supplementation (3 g\/d) and bone health in older women: a 2-year randomized placebo-controlled trial (n=200, osteopenia). J Gerontol A Biol Sci Med Sci<\/i> 2020;75:931\u2013938. doi:10.1093\/gerona\/glz162<\/span> INDEPENDENT \u2014 Univ. S\u00e3o Paulo<\/span><\/li>\n <li>Creatine monohydrate for lean mass, strength, and bone density in postmenopausal women: systematic review and meta-analysis (searches to Aug 2025). PubMed<\/i> 42141930. INDEPENDENT<\/span><\/li>\n <li>Lyoo IK, Yoon S, Kim TS, et al. Oral creatine monohydrate augmentation for enhanced response to an SSRI in women with major depressive disorder: randomized double-blind placebo-controlled trial (n=52). Am J Psychiatry<\/i> 2012;169:937\u2013945. doi:10.1176\/appi.ajp.2012.12010009<\/span> INDEPENDENT<\/span><\/li>\n <li>Yoon S, Kim JE, et al. Effects of creatine monohydrate augmentation on brain metabolic and network outcome measures in women with MDD. Biol Psychiatry<\/i> 2016;80:439\u2013447. doi:10.1016\/j.biopsych.2015.11.027<\/span> INDEPENDENT<\/span><\/li>\n <li>Kondo DG, Forrest LN, et al. Creatine target engagement with brain bioenergetics: dose-ranging \u00b3\u00b9P-MRS study of adolescent females with SSRI-resistant depression (2\/4\/10 g\/d). Amino Acids<\/i> 2016;48:1941\u20131954. doi:10.1007\/s00726-016-2194-3<\/span> INDEPENDENT \u2014 NIMH<\/span><\/li>\n <li>Fares BJ, Zhou C, Fabiano N, et al. The effect of creatine monohydrate on mental disorders: systematic review of RCTs. Can J Psychiatry<\/i> 2026. doi:10.1177\/07067437251408171<\/span> INDEPENDENT (cluster co-authors noted)<\/span><\/li>\n <li>Dickinson H, Davies-Tuck M, Ellery SJ, et al. Maternal creatine in pregnancy: a retrospective cohort study (n=287). BJOG<\/i> 2016;123:1830\u20131838. doi:10.1111\/1471-0528.14237<\/span> INDEPENDENT<\/span><\/li>\n <li>de Guingand DL, Palmer KR, Callahan DL, Snow RJ, Davies-Tuck ML, Ellery SJ. Creatine and pregnancy outcomes (CPO): prospective cohort study of creatine metabolism in low-risk pregnant females (n=282). Am J Clin Nutr<\/i> 2024;119:838\u2013849. doi:10.1016\/j.ajcnut.2023.11.006<\/span> INDEPENDENT \u2014 Hudson Institute\/Monash<\/span><\/li>\n <li>Muccini AM, Tran NT, de Guingand DL, et al. Creatine metabolism in female reproduction, pregnancy and newborn health. Nutrients<\/i> 2021;13:490. doi:10.3390\/nu13020490<\/span> INDEPENDENT<\/span><\/li>\n <li>Naidu M, de Guingand DL, et al. Open label, dose escalation trial of creatine monohydrate in pregnancy (first human supplementation PK data). JISSN<\/i> 2025;22:2533652. doi:10.1080\/15502783.2025.2533652<\/span> INDEPENDENT \u2014 Monash<\/span><\/li>\n <li>Freeman AK, Dyson RM, Berry MJ, Ellery SJ. Safety of maternal creatine supplementation: guinea pig model of full-term pregnancy. JISSN<\/i> 2025;22:2533674. doi:10.1080\/15502783.2025.2533674<\/span> INDEPENDENT \u2014 preclinical<\/span><\/li>\n <\/ol>\n\n <h3>Men\u2019s health, hair & hormones<\/h3>\n <ol>\n <li>Lak M, Forbes SC, Ashtary-Larky D, et al. Does creatine cause hair loss? A 12-week randomized controlled trial. JISSN<\/i> 2025;22:2495229. doi:10.1080\/15502783.2025.2495229<\/span> ISSN-CLUSTER (only direct evidence; concordant with 12 independent hormone datasets)<\/span><\/li>\n <li>van der Merwe J, Brooks NE, Myburgh KH. Three weeks of creatine monohydrate supplementation affects DHT:T ratio in college-aged rugby players. Clin J Sport Med<\/i> 2009;19:399\u2013404. doi:10.1097\/JSM.0b013e3181b8b52f<\/span> INDEPENDENT \u2014 the single unreplicated origin of the myth<\/span><\/li>\n <li>Antonio J, Candow DG, Forbes SC, et al. Common questions and misconceptions about creatine supplementation. JISSN<\/i> 2021;18:13. doi:10.1186\/s12970-021-00412-w<\/span> ISSN-CLUSTER \u2014 consensus document<\/span><\/li>\n <li>Antonio J, et al. Part II: Common questions and misconceptions about creatine supplementation. JISSN<\/i> 2024;21:2441760. doi:10.1080\/15502783.2024.2441760<\/span> ISSN-CLUSTER \u2014 consensus document<\/span><\/li>\n <\/ol>\n\n <h3>Skin \u2014 flagged commercial<\/h3>\n <ol>\n <li>Peirano RI, Achterberg V, et al. Dermal penetration of creatine from a face-care formulation containing creatine, guarana and glycerol: antiwrinkle and antisagging efficacy in male subjects. J Cosmetic Dermatol<\/i> 2011;10:273\u2013281. doi:10.1111\/j.1473-2165.2011.00579.x<\/span> COMMERCIAL \u2014 Beiersdorf<\/span><\/li>\n <li>Lenz H, et al. The creatine kinase system in human skin: protective effects of creatine against oxidative and UV damage. J Invest Dermatol<\/i> 2005;124:443\u2013452. doi:10.1111\/j.0022-202X.2004.23522.x<\/span> COMMERCIAL \u2014 Beiersdorf<\/span><\/li>\n <li>Knott A, Fischer F, et al. Folic acid and creatine improve the firmness of human skin in vivo. J Cosmetic Dermatol<\/i> 2008. COMMERCIAL \u2014 Beiersdorf<\/span><\/li>\n <\/ol>\n\n <h3>Co-ingestion & interactions<\/h3>\n <ol>\n <li>Elosegui S, et al. Interaction between caffeine and creatine when used as concurrent ergogenic supplements: systematic review (10 studies). Int J Sport Nutr Exerc Metab<\/i> 2022;32:285\u2013295. doi:10.1123\/ijsnem.2021-0262<\/span> INDEPENDENT<\/span><\/li>\n <li>Trexler ET, Smith-Ryan AE. Creatine and caffeine: considerations for concurrent supplementation. Int J Sport Nutr Exerc Metab<\/i> 2015;25:607\u2013623. doi:10.1123\/ijsnem.2014-0193<\/span> ISSN-CLUSTER<\/span><\/li>\n <li>Vandenberghe K, et al. Caffeine counteracts the ergogenic action of muscle creatine loading. J Appl Physiol<\/i> 1996;80:452\u2013457. doi:10.1152\/jappl.1996.80.2.452<\/span> INDEPENDENT \u2014 origin of the caffeine debate, contested since<\/span><\/li>\n <li>Green AL, Hultman E, Macdonald IA, et al. Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans. Am J Physiol<\/i> 1996;271:E821\u2013E826. doi:10.1152\/ajpendo.1996.271.5.E821<\/span> INDEPENDENT<\/span><\/li>\n <li>Steenge GR, Simpson EJ, Greenhaff PL. Protein- and carbohydrate-induced augmentation of whole body creatine retention in humans. J Appl Physiol<\/i> 2000;89:1165\u20131171. doi:10.1152\/jappl.2000.89.3.1165<\/span> INDEPENDENT<\/span><\/li>\n <li>Synergistic effects of creatine, carbohydrates and protein on repeated sprint performance (4-group RCT, n=60). Scientific Reports<\/i> 2026. doi:10.1038\/s41598-026-44278-x<\/span> INDEPENDENT<\/span><\/li>\n <li>Stecker RA, Harty PS, Jagim AR, Candow DG, Kerksick CM. Timing of ergogenic aids and micronutrients on muscle and exercise performance. JISSN<\/i> 2019;16:37. doi:10.1186\/s12970-019-0304-9<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n\n <h3>Adjacent amino-acid co-supplements<\/h3>\n <ol>\n <li>Ashtary-Larky D, Candow DG, Forbes SC, et al. Effects of creatine and \u03b2-alanine co-supplementation on exercise performance and body composition: systematic review (7 RCTs, n=263). Nutrients<\/i> 2025;17(13):2074. doi:10.3390\/nu17132074<\/span> ISSN-CLUSTER<\/span><\/li>\n <\/ol>\n<\/section>\n\n<footer>\n SCOPE & DISCLAIMER.<\/strong> Companion dossier to \u201cHuman Nutrient Requirements \u2014 The Certainty Pyramid,\u201d same visual grammar: width = evidentiary weight, colour depth = certainty, solid fills only, five-step ramp #093644 \u2192 #A63525. Compiled from live literature search, August 2026. All effect estimates, confidence intervals and trial figures require independent verification against primary sources before publication or clinical use. This document is a scientific literature review, not individualised medical or nutritional advice; anyone pregnant, under 18, with kidney or liver disease, or taking medication should involve a physician or registered dietitian before beginning supplementation.<\/p>\n<\/footer>\n\n<\/div>\n<\/body>\n<\/html>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"Creatine on the Certainty Pyramid – Requirements, Risks and Myths Rebuilt from Primary Literature (2015\u20132026) EVIDENCE REVIEW \u00b7 SUPPLEMENT DOSSIER N\u00ba 2 \u00b7 COMPANION TO \u201cHUMAN NUTRIENT REQUIREMENTS\u201d Facts About Creatine Requirements, kidneys (including the full long-term record), water, liver, skin, muscle, brain, women\u2019s health (bone, mood, pregnancy, menopause \u2014 trial by trial), men\u2019s health, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"elementor_canvas","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[37,26,28,27,25,39,38],"class_list":["post-821","post","type-post","status-publish","format-standard","hentry","category-text","tag-creatine","tag-food","tag-food-2026","tag-nutrition","tag-nutrition-2026","tag-nutritious-facts","tag-supplement"],"_links":{"self":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts\/821","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/comments?post=821"}],"version-history":[{"count":4,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts\/821\/revisions"}],"predecessor-version":[{"id":826,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/posts\/821\/revisions\/826"}],"wp:attachment":[{"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/media?parent=821"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/categories?post=821"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rezaraza.com\/fr\/wp-json\/wp\/v2\/tags?post=821"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}