Does Creatine Cause Hair Loss? The Original Study, and Everything Since
Published by AmpleLab Research
Nearly every claim that creatine causes hair loss traces back to one study: 20 rugby players, a South African university, and a single 2009 paper measuring hormone changes over three weeks. That paper is real, and its finding was real. What's less often reported is what happened afterward: a body of subsequent research, culminating in a 2025 trial that directly measured hair follicle health rather than just blood hormones, that has not reproduced the original result.
This article goes through the original study in full, the studies that followed it, and where that leaves the actual answer, which is more nuanced than either "creatine definitely causes hair loss" or "this has been completely debunked."
Why DHT Is the Relevant Hormone Here
Dihydrotestosterone (DHT) is the androgen that drives androgenetic alopecia in genetically susceptible follicles, converted from testosterone by the enzyme 5-alpha reductase. It's a more potent activator of androgen receptor signalling than testosterone itself, and it's the hormone finasteride and dutasteride work by suppressing. Full detail on the mechanism is covered in our article on DHT and the follicle, rather than repeated here.
Because DHT is the specific hormone implicated in AGA, any supplement claimed to raise it attracts attention from anyone managing or worried about hair loss. Creatine's reputation on this front rests almost entirely on the single study covered next.
The Original Study, in Full
Twenty college-aged male rugby players at Stellenbosch University, South Africa, completed a double-blind, placebo-controlled crossover trial with a 6-week washout between arms. The creatine arm loaded with 25g/day creatine monohydrate (plus 25g/day glucose) for 7 days, then dropped to 5g/day creatine (plus 25g/day glucose) for a further 14 days. The placebo arm received matched glucose alone.
Serum DHT increased 56% after the 7-day loading phase and remained 40% above baseline after the 14-day maintenance phase, both statistically significant versus placebo. Total testosterone did not change significantly at any point. No hair, skin, or follicle outcome of any kind was measured; this was a blood hormone study only.
This is a real, methodologically reasonable study: randomised, double-blind, placebo-controlled, with each participant serving as their own control via the crossover design. It isn't a case of a poorly run trial producing a spurious result. The study found a statistically significant increase in serum DHT under the conditions tested.
What it doesn't establish, and never claimed to, is whether that hormone change translates into any actual hair outcome. A 40% rise in serum DHT is a measurable physiological change; whether it's large enough, sustained enough, or reaches follicle tissue in a way that measurably affects hair is a separate question the study wasn't designed to answer.
What Limits How Far This Study Can Be Read
A sample of 20 (with some sources reporting 16 completers) is small for hormone research, where individual variability is considerable. It's also a single study: no independent group had, at that point, attempted to reproduce the finding under different conditions, different populations, or different creatine protocols. One study, however well conducted, establishes a finding worth investigating further; it doesn't establish a settled fact on its own; that's true of any single trial in any area of science, not a specific criticism of this one.
The population is also specific: competitive rugby players in-season, undergoing regular resistance and contact training. Exercise itself produces acute hormonal responses, and whether the same DHT pattern would appear in a sedentary person, a recreational lifter, or someone of a different age range wasn't tested here.
What the Wider Literature Shows
Creatine is one of the most heavily studied supplements in sports nutrition, and its hormonal effects specifically have been reviewed more than once since 2009.
A systematic review and meta-analysis of randomised controlled trials measuring the effect of creatine supplementation on circulating testosterone and DHT, pooling across the available trial data rather than relying on any single study. This is the closest thing to a comprehensive answer the literature currently has for the hormone-level question, independent of the hair-specific question addressed by the 2025 trial below.
Separately, a 2021 review specifically addressing common creatine misconceptions took direct aim at the hair loss claim.
This review states directly that "the vast majority of speculation regarding the relationship between creatine supplementation and hair loss/baldness stems from a single study," correctly citing van der Merwe's exact figures (56% after loading, 40% above baseline after maintenance) rather than a vaguer secondhand version. Its conclusion: "the current body of evidence does not indicate that creatine supplementation increases total testosterone, free testosterone, DHT or causes hair loss."
Worth being precise about what that conclusion is and isn't: it's a statement that the broader body of evidence doesn't support the claim, not a statement that the 2009 finding was wrong or that DHT elevation from creatine is impossible. The review is explicit that further properly designed research, measuring DHT and hair outcomes together, was still needed at the time it was written.
The Study That Actually Tested Hair, Directly
The gap the 2021 review identified, no study measuring both DHT and actual hair follicle health, was closed in 2025 by a trial led by Grant Tinsley's group at Texas Tech University, registered in advance on ClinicalTrials.gov before results were known.
Forty-five resistance-trained men aged 18-40 were randomised to creatine monohydrate (5g/day) or a maltodextrin placebo for 12 weeks, maintaining their normal diet and training. Thirty-eight completed the study. Blood was drawn at baseline and 12 weeks for total testosterone, free testosterone, and DHT; hair follicle health was assessed directly using trichogram-based measurement, alongside global photography.
Result: no significant group-by-time interaction for any hormone or hair-related outcome. Total testosterone rose in both groups over the 12 weeks (creatine +124 ± 149 ng/dL; placebo +216 ± 203 ng/dL), and free testosterone fell in both groups, but neither change differed meaningfully between creatine and placebo, meaning these shifts reflect something other than the supplement itself. DHT levels, the DHT:testosterone ratio, and hair growth parameters showed no significant difference between groups at any point. The authors' own conclusion: this was the first study to directly assess hair follicle health following creatine supplementation, and it provides evidence against the claim that creatine contributes to hair loss.
This trial has its own limitations worth naming rather than glossing over. Thirty-eight completers is a modest sample for hormone and hair research. It didn't screen for genetic predisposition to androgenetic alopecia, meaning the group could easily have included people with low baseline susceptibility regardless of any DHT change. The trichogram-based hair assessment tools used, while standard, are less sensitive than some newer imaging approaches. And it used a flat 5g/day protocol without the loading phase the original 2009 study used, so it doesn't directly replicate that specific dosing pattern, only a more typical maintenance-level regimen.
Even accounting for those limitations, it's a meaningfully stronger piece of evidence than anything that existed before it, precisely because it's the only study in either direction to actually measure hair, rather than inferring hair effects from a blood hormone change alone.
Where This Actually Leaves the Answer
The honest summary: one small, well-conducted 2009 study found a real DHT increase from creatine loading in rugby players, using a protocol with a high initial loading dose. No subsequent study, including a purpose-built 2025 trial specifically designed to close this exact gap, has reproduced a DHT change from creatine, and the only study to measure actual hair outcomes found no effect on those either. Neither the subsequent systematic review evidence nor the direct hair trial reproduced the original study's finding.
The Honest Position
Absence of replication isn't the same as proof the original finding was wrong; it's possible the 2009 result reflects something specific to that population, that loading protocol, or simple sampling variation in a small trial. What can be said with more confidence is that the current weight of evidence, including the only study to ever directly measure hair, doesn't support creatine as a cause of hair loss for most people. That's a considerably more reassuring position than the original headline implied, without overstating it as a fully closed question.
Where This Leaves Practical Use
Creatine monohydrate's benefits for strength, lean mass, and training performance are supported by a genuinely large body of research, among the most extensively studied supplements in sports nutrition. Discontinuing it on hair-loss grounds alone means giving up well-established benefits in exchange for a concern the best available direct evidence doesn't currently support.
If you have a strong family history of androgenetic alopecia and want to be cautious regardless, monitoring your own hair over time while using creatine is a reasonable personal choice, and if you're already managing AGA through an established protocol, that's a separate question from creatine entirely; our hair loss protocol framework covers how topical actives, DHT-targeted treatments, and vascular support fit together, independent of anything covered in this article.
Frequently Asked Questions
Was the original 2009 creatine-DHT study ever discredited or retracted?
No. It remains a published, peer-reviewed, methodologically sound study. It simply hasn't been reproduced by later research, including studies specifically designed to test the same question with better outcome measures.
Has any study directly measured whether creatine affects hair, not just hormones?
Yes, one: Lak et al. 2025, a 12-week randomised controlled trial that measured DHT alongside actual trichogram-based hair follicle assessment and global photography. It found no significant difference between creatine and placebo on any hormone or hair measure. It's the only study in either direction to test hair outcomes directly.
Should I stop taking creatine if I'm worried about hair loss?
The current evidence, including the only direct hair trial, doesn't support creatine as a cause of hair loss for most people. If you're already noticing shedding or thinning, that's worth investigating on its own terms, distinct from whether creatine is involved, since AGA and other causes of hair loss are common regardless of supplement use.
Does the loading phase matter? The 2025 study didn't use one.
That's a genuine gap worth naming: the 2025 trial used a flat 5g/day dose throughout, while the original 2009 study used a 25g/day loading week before dropping to 5g/day. Whether a loading phase specifically produces a different, larger, or more transient DHT response than steady-state dosing hasn't been directly tested against a hair outcome. Most long-term creatine users don't maintain a loading dose indefinitely, so the 2025 protocol reflects more typical real-world use, even though it doesn't perfectly replicate the original study's exact dosing pattern.
Is there a difference between creatine and hair loss risk in men already on finasteride or dutasteride?
This hasn't been specifically studied. If a 5-alpha reductase inhibitor is already substantially suppressing DHT production, any small additional DHT change from creatine, even if one existed, would plausibly matter less in absolute terms. This is reasoning from mechanism rather than a tested combination, so treat it as a plausible inference, not a demonstrated finding.
Selected Research
This article is provided for educational purposes and does not constitute medical advice. AmpleLab does not sell or endorse any specific creatine product. Consult a GP or dietitian before starting any new supplement, particularly if you have existing health conditions.
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