Study Overview
Citation: van der Merwe J, Brooks NE,”;”; KH. (2009).
Three weeks of creatine monohydrate supplementation affects dihydrotestosterone to testosterone ratio in college-aged rugby players. Clinical Journal of Sport Medicine, 19(5), 399-404.
This is the single study that launched the widespread concern about creatine causing hair loss. It is one of the most misinterpreted studies in sports nutrition research.
Understanding what it actually found — and what it did not find — is essential for informed decision-making.
Study Design and Methods
The study was a randomised, double-blind, placebo-controlled trial involving 20 college-aged male rugby players from South Africa.
The protocol consisted of a 7-day loading phase (25g creatine per day) followed by a 14-day maintenance phase (5g per day).
Researchers measured serum testosterone, dihydrotestosterone (DHT), and the testosterone-to-DHT ratio at baseline, after loading (day 7), and after maintenance (day 21).
Key Findings
What the Study Found
During the loading phase, DHT levels increased by approximately 56% from baseline. During the maintenance phase, DHT remained elevated at 40% above baseline.
The testosterone-to-DHT ratio decreased, suggesting increased conversion of testosterone to DHT via the 5-alpha reductase enzyme.
Importantly, total testosterone levels did not change significantly.
The effect appeared to be specifically on the conversion rate from testosterone to DHT, not on overall androgen production.
What the Study Did NOT Find
The study did not measure hair loss, hair thickness, hair follicle health, or any scalp-related outcome.
There was zero observation of actual hair loss in any participant.
The connection between this DHT finding and hair loss is entirely theoretical — based on the known role of DHT in androgenetic alopecia (male pattern baldness) in genetically predisposed individuals.
Critical Limitations
- Never replicated — No other study has shown creatine increases DHT
- No hair loss measured — The study measured hormones only, not hair outcomes
- Small sample size — Only 20 participants
- Short duration — 21 days total
- High loading dose — 25g/day is higher than the standard 20g/day loading protocol
- Single population — Young male rugby players; cannot generalise to all demographics
- DHT within normal range — Even with the increase, DHT levels remained within normal physiological limits
- Exercise confound — Rugby training itself affects hormone levels
The DHT-Hair Loss Connection Explained
DHT is a potent androgen that plays a role in male pattern baldness — but only in individuals who are genetically predisposed.
The mechanism involves DHT binding to receptors in hair follicles, causing miniaturisation and eventual hair loss.
However, several important caveats apply.
Normal daily DHT fluctuations from exercise, diet, and stress can equal or exceed the increase seen in this study.
Millions of men with normal DHT levels experience hair loss. Many men with elevated DHT have full heads of hair.
Genetic predisposition is the primary determinant, not DHT levels alone.
What the Broader Research Shows
Multiple studies examining creatine and hormonal profiles have not found significant changes in DHT or testosterone.
A 2021 systematic review and meta-analysis examined 22 studies on creatine and testosterone, finding no significant effect on total testosterone, free testosterone, or DHT levels.
Malaysian Relevance
Hair loss is a significant concern across all demographics in Malaysia.
This study’s findings should be viewed in context: a single unreplicated study with no actual hair loss measurement.
Malaysian men concerned about hair loss should consider that genetics, age, and overall health are far more significant factors than creatine supplementation.
Where This Fits in the Evidence
The whole hair-loss worry rests on this one trial in 20 rugby players, where the testosterone-to-DHT ratio shifted during loading while total testosterone held steady. That makes van der Merwe et al. a preliminary signal about a hormone ratio, not evidence of hair loss — which the study never measured — and it has not been replicated in the years since. Set against the wider safety and hormone literature gathered in our research library, a single unreplicated finding carries limited weight. The honest reading is that the DHT-to-baldness link here stays theoretical, and genetic predisposition remains the dominant factor.
Sources and References
- van der Merwe J, et al. (2009). Three weeks of creatine monohydrate supplementation affects DHT to testosterone ratio. CJSM, 19(5), 399-404.
- Kreider RB, et al. (2017). ISSN position stand. JISSN, 14, 18.
- Antonio J, et al. (2021). Common questions and misconceptions about creatine supplementation. JISSN, 18, 13.
Further Reading
- creatine dosage guide
- creatine safety profile
- creatine monohydrate
- creatine loading phase
- buying creatine in Malaysia
- creatine for teenagers
Sources & References
Full citations available in our Research Library.