The Origins of a Concern: The 2009 Rugby Study
The widespread concern linking creatine to elevated dihydrotestosterone (DHT) levels originates from a single, small-scale randomized controlled trial published in 2009. In this study, 20 college-aged male rugby players were given either a creatine supplement or a placebo for three weeks, including an initial loading phase and a maintenance phase.
The results indicated a 56% increase in DHT levels during the seven-day loading phase in the creatine group, which remained 40% above baseline during the two-week maintenance period. The study's authors theorized that creatine might enhance the conversion of testosterone to DHT, a more potent androgen.
However, it's crucial to consider the limitations of this specific study:
- Small sample size: The study involved only 20 participants, making the results less statistically robust and potentially influenced by individual variation.
- Lack of direct hair loss measurement: Researchers measured hormone levels but did not assess actual hair loss, thinning, or follicle health.
- Inconsistent findings: The results of the 2009 study have not been consistently replicated in subsequent research.
- Possibility of supplement contamination: Some experts have raised the possibility that the original results could have been influenced by contaminated supplements, a common issue in the supplement industry.
Subsequent Research Refutes the Connection
In the years following the 2009 study, numerous larger and more rigorous investigations have been conducted to determine creatine's hormonal impact. The vast majority of these studies have not found a link between creatine supplementation and increased DHT or hair loss.
For example, a randomized controlled trial published in April 2025 specifically addressed this concern by evaluating the effects of creatine supplementation on both androgen levels and hair follicle health over a 12-week period. This study, which involved 38 resistance-trained men, found no significant differences in total testosterone, free testosterone, DHT, or the DHT-to-testosterone ratio between the creatine and placebo groups. Crucially, the researchers used advanced tools to directly assess hair follicle health and found no decline in hair density, follicle count, or thickness in the creatine group.
In addition, systematic reviews synthesizing the existing body of literature have reached similar conclusions, reinforcing that creatine does not significantly alter hormone levels in a way that would trigger hair loss.
The Role of Genetics in Hair Loss
It is important to remember that DHT is only one piece of the complex puzzle of hair loss, and its effects are heavily influenced by genetics. The primary driver of male pattern baldness (androgenic alopecia) is a genetic predisposition that makes hair follicles sensitive to DHT. For those with this genetic sensitivity, the presence of DHT can cause hair follicles to shrink, leading to thinning and eventual loss.
Creatine itself does not cause this sensitivity; it is a supplement that supports energy production in the muscles. While DHT is known to affect hair follicles, the notion that creatine can cause a significant enough hormonal shift to trigger or accelerate hair loss has not been substantiated by the broader scientific community.
A Comparative Look at Creatine's Hormonal Effects
To better understand the contrasting evidence, here is a comparison of the 2009 study with the broader body of research on creatine and hormone levels.
| Feature | 2009 DHT Study | Later, More Extensive Research |
|---|---|---|
| Sample Size | Small (n=20 rugby players). | Much larger sample sizes across multiple studies. |
| Study Duration | Short (3 weeks). | Many studies lasting longer, up to 12 weeks or more. |
| DHT Findings | Temporary 56% increase in DHT during loading, remaining 40% above baseline. | No significant changes in DHT levels reported in most studies. |
| Testosterone Findings | No change in testosterone levels. | Majority show no significant effect on testosterone. |
| Hair Loss Assessment | None; measured hormone levels only. | Recent studies (e.g., 2025) directly measured hair follicle health and density. |
| Replication | Not replicated by subsequent research. | Widely supported consensus that creatine does not cause hair loss. |
Additional Considerations and Conclusion
Beyond the DHT debate, it's worth noting that genetics, lifestyle, and overall health are far more significant factors influencing hair loss. Nutritional deficiencies, high stress levels, and various medical conditions can all play a role in hair thinning.
In conclusion, while a single, limited study from 2009 initially raised concerns about creatine and DHT levels, the extensive body of research that followed has largely debunked this link. Current evidence suggests that for most healthy individuals, creatine does not significantly increase DHT or cause hair loss. Concerns over creatine and hair loss primarily stem from a scientific misinterpretation of that early, unreplicated finding.
For those genetically predisposed to androgenic alopecia, it is always wise to consult a healthcare professional or dermatologist if you notice signs of hair thinning. However, based on the available scientific literature, there is no strong evidence to support avoiding creatine out of fear of hair loss. Creatine remains one of the most well-researched and safe supplements for improving athletic performance.
Factors That Influence Hair Health and Loss
- Genetics and Family History: The most critical determinant of androgenic alopecia, or pattern baldness.
- Hormonal Changes: Natural hormonal shifts and conditions like thyroid issues can impact hair.
- Nutritional Deficiencies: A lack of key vitamins and minerals can contribute to hair thinning.
- Chronic Stress: High and prolonged stress levels can lead to various forms of hair loss.
- Medications: Certain medications can have hair loss as a side effect.
- Overall Health: General health, aging, and specific medical conditions play significant roles.
Creatine Safety Profile
- Generally Safe: Creatine is considered safe for most healthy individuals when taken at appropriate doses for up to five years.
- Potential for Water Weight Gain: A common short-term side effect, as creatine can increase water retention in muscles.
- Gastrointestinal Upset: Some users report stomach discomfort, nausea, or diarrhea.
- Kidney Concerns: Individuals with pre-existing kidney conditions should consult a doctor, though research does not show adverse effects on healthy kidneys.
