“Creatine accelerates hair loss.”

• The single study most often cited in support: van der Merwe, Brooks & Myburgh (Clinical Journal of Sport Medicine, 2009) found that in 20 college-aged male rugby players, 7 days of creatine loading (25 g/day) raised serum dihydrotestosterone (DHT) by ~56% and it remained ~40% above baseline after 14 days of 5 g/day maintenance, while total testosterone was unchanged — raising the DHT:testosterone ratio.
• DHT is the androgen causally implicated in androgenetic alopecia; 5-alpha-reductase inhibitors (finasteride, dutasteride) treat male-pattern baldness precisely by lowering DHT. So a genuine, sustained DHT elevation would be a biologically plausible route to faster hair loss in genetically susceptible men.
• Large volumes of anecdotal reports (forums, social media, some clinician anecdotes) describe increased shedding after starting creatine, which keeps the hypothesis alive in popular discourse.
• No long-term trial has specifically tracked hair density/shedding in creatine users for years, so the absence of evidence of harm is partly an absence of dedicated evidence rather than proof of safety.

• No published study has ever measured hair loss, hair density, or diagnosed androgenetic alopecia as an outcome of creatine supplementation. The claim that creatine 'accelerates hair loss' rests entirely on an inference from one hormone-ratio finding, not on any hair data.
• The 2009 rugby-player result has not been replicated in over 15 years. It was small (n=20), was a secondary finding, and the DHT values reportedly remained within the normal physiological reference range.
• Antonio et al., 'Common questions and misconceptions about creatine supplementation' (Journal of the International Society of Sports Nutrition, 2021) reviewed the hormone literature and concluded creatine does not reliably increase testosterone or DHT and that the balance of evidence does not support a hair-loss effect; the great majority of studies measuring androgens found no change.
• The ISSN position stand on creatine (Kreider et al., 2017) — the most comprehensive safety review of the supplement — lists no androgenic or dermatologic/hair adverse effects among documented risks, concluding creatine monohydrate is safe for short- and long-term use.
• Creatine has no known pharmacological pathway to androgen synthesis: it is not a steroid precursor and does not inhibit or activate 5-alpha-reductase by any established mechanism.
• Heavy confounding explains the anecdotes: creatine users skew male, young-to-middle-aged, and gym-going — the exact demographic entering androgenetic alopecia — and a subset also use anabolic steroids, which genuinely do accelerate balding. Correlation in self-reports is not causation.
• Mainstream clinical and government reviews (e.g., NIH Office of Dietary Supplements) do not list hair loss as an established effect of creatine.

82/100 — the lab’s own confidence in the score above, not a second reading of the claim.

Journal of the International Society of Sports Nutrition (Antonio et al., 2021)journal · 85 · Journal of the International Society of Sports Nutrition — ISSN Position Stand (Kreider et al., 2017)journal · 85 · PubMed / Clinical Journal of Sport Medicine (van der Merwe et al., 2009)journal · 88 · NIH Office of Dietary Supplementsgov · 95 · Examine.comother · 78

• A small 2009 randomized study of 20 college-aged rugby players found that creatine supplementation increased dihydrotestosterone (DHT) and the DHT:testosterone ratio over 3 weeks. Because DHT is biologically involved in androgenetic alopecia, this is the main indirect evidence often cited for the claim.
• Androgenetic alopecia is androgen/DHT-sensitive, so a sustained creatine-caused rise in DHT, if real and clinically meaningful, could be a plausible mechanism for accelerating genetically predisposed hair loss. However, the 2009 study did not measure hair shedding, hair density, or baldness progression.

• No good human trial evidence shows that creatine supplementation directly causes or accelerates hair loss. The main pro-claim study measured hormones, not hair outcomes, was small, short, and has not established a clinical hair-loss effect.
• A 2021 Journal of the International Society of Sports Nutrition review specifically addresses the hair-loss claim and concludes that current evidence does not support creatine causing hair loss or baldness; it notes the concern largely comes from the single DHT study and that broader testosterone-related findings do not show a consistent androgen-raising effect.
• MedlinePlus’ creatine safety summary lists recognized concerns and side effects but does not identify hair loss as an established adverse effect.
• Overall, the claim as written states a causal effect too strongly. A more accurate statement would be: 'There is a theoretical concern based on one small DHT study, but creatine has not been shown to accelerate hair loss.'

84/100 — the lab’s own confidence in the score above, not a second reading of the claim.

Clinical Journal of Sport Medicine / PubMedjournal · 84 · Journal of the International Society of Sports Nutrition / PubMed Centraljournal · 91 · StatPearls / NCBI Bookshelfgov · 82 · MedlinePlusgov · 88

• A 2009 study by van der Merwe et al. on college-aged rugby players found that a creatine loading phase followed by maintenance increased serum levels of dihydrotestosterone (DHT) by over 40%.
• Because DHT is an androgen hormone known to bind to hair follicles and drive male pattern baldness, this isolated finding led to the theoretical hypothesis that creatine could accelerate hair loss.

• The 2009 study only measured hormone levels, not actual hair loss or follicular miniaturization. Furthermore, the subjects' DHT levels remained well within the normal clinical range.
• A comprehensive 2021 systematic review published by the International Society of Sports Nutrition (ISSN) examined the literature and concluded that there is no scientific evidence that creatine supplementation causes or accelerates hair loss.
• Out of numerous randomized controlled trials evaluating creatine's effect on androgens, the vast majority have failed to replicate the significant spikes in free testosterone or DHT required to trigger accelerated alopecia.

95/100 — the lab’s own confidence in the score above, not a second reading of the claim.

National Center for Biotechnology Information (NCBI) / Journal of the International Society of Sports Nutritionjournal · 95 · PubMed (Clinical Journal of Sport Medicine)journal · 85 · Healthlinenews · 80

• A small 2009 study of 20 college-age rugby players reported a 56% rise in serum DHT after seven days of high-dose creatine loading (25 g/day), with DHT remaining 40% above baseline after two weeks of maintenance dosing. Because elevated DHT is biologically associated with androgenetic hair loss, this provides a plausible—but indirect—mechanism for concern.[4][5]
• The 2009 study measured hormone changes, not hair loss itself, and its findings have not been replicated in subsequent research.[4]

• A 2025 double-blind randomized controlled trial assigned 45 resistance-trained men to 5 g/day of creatine or placebo for 12 weeks. It found no significant between-group differences in DHT, the DHT-to-testosterone ratio, hair density, follicular-unit count, cumulative hair thickness, or other hair-growth measures.[2][9]
• A 2021 evidence review concluded that the available research did not indicate that creatine increases DHT or causes hair loss, noting that no human study had reported hair loss or baldness caused by creatine.[4]
• The evidence supporting the claim is based primarily on one small, short-duration, indirect hormone study; the newer randomized trial directly assessed hair outcomes and found no adverse effect.[2][4][9]

94/100 — the lab’s own confidence in the score above, not a second reading of the claim.

PubMedjournal · 98 · Journal of the International Society of Sports Nutritionjournal · 95 · Journal of the International Society of Sports Nutritionjournal · 94 · PubMedjournal · 98 · Cleveland Clinicedu · 88

• A 2009 randomized trial in 20 college rugby players found creatine loading raised serum DHT ~56% (still remaining elevated ~40% after a maintenance phase); DHT is the androgen most strongly linked to androgenetic alopecia in genetically susceptible men.
• Anecdotal reports from some users (especially those with a family history of male-pattern baldness) describe faster thinning that temporally coincides with creatine use, which is mechanistically consistent with a DHT pathway.

• No randomized trial has ever measured actual hair-loss outcomes (shedding counts, density, or follicular miniaturization) and shown creatine accelerates them.
• The 2009 DHT study was small, short, did not assess hair, and left DHT inside normal clinical ranges; it has not been replicated with hair endpoints.
• Major safety reviews and the International Society of Sports Nutrition state there is insufficient evidence that creatine causes or accelerates hair loss; decades of creatine trials have not identified hair loss as a consistent adverse effect.

78/100 — the lab’s own confidence in the score above, not a second reading of the claim.

Clinical Journal of Sport Medicinejournal · 85 · Journal of the International Society of Sports Nutritionjournal · 92 · Journal of the International Society of Sports Nutritionjournal · 90 · Examine.comother · 88