Creatine does not reduce testosterone. Across more than a dozen studies examining creatine supplementation at doses ranging from 3 to 25 grams per day for up to 12 weeks, the consistent finding is that creatine has no meaningful effect on testosterone levels. The concern likely stems from a single 2009 study that found changes in a related hormone, but the broader body of evidence doesn’t support creatine lowering (or raising) testosterone in any clinically significant way.
Where the Concern Comes From
In 2009, a study on college-aged rugby players found that three weeks of creatine supplementation increased levels of dihydrotestosterone (DHT), a more potent form of testosterone, by 56% during a loading phase and 40% during a maintenance phase. The ratio of DHT to testosterone also shifted upward. Crucially, testosterone itself did not change in that study. The authors speculated that creatine might speed up the conversion of testosterone into DHT, which sparked widespread concern online, particularly around hair loss and hormonal disruption.
That single study, involving just 16 participants who completed the protocol, has never been replicated. It remains an outlier in the research literature, yet it continues to drive most of the worry you’ll find in forums and social media posts about creatine and hormones.
What the Broader Evidence Shows
At least 12 additional studies have measured testosterone in people taking creatine. Ten of them found no change whatsoever. Two reported small increases in total testosterone after six or seven days of supplementation, but these increases were too small to have any real physiological effect. In five of those studies, researchers also measured free testosterone, the form your body actually uses. None found an increase.
A 2021 review published in the Journal of the International Society of Sports Nutrition evaluated all of this evidence together and concluded plainly: the current body of evidence does not indicate that creatine supplementation increases total testosterone, free testosterone, or DHT.
In other words, creatine doesn’t lower testosterone, and it doesn’t meaningfully raise it either. It appears to be hormonally neutral.
Creatine, DHT, and Hair Loss
The DHT finding from 2009 also fueled a persistent rumor that creatine causes hair loss, since DHT is involved in pattern baldness. A 2025 randomized controlled trial put this directly to the test for the first time. Forty-five resistance-trained men took either 5 grams of creatine per day or a placebo for 12 weeks. Researchers measured total testosterone, free testosterone, DHT, and the DHT-to-testosterone ratio at both the start and end of the study. They also assessed actual hair follicle health using specialized imaging, including hair density, follicular unit count, and cumulative hair thickness.
The results: no differences between the creatine and placebo groups on any hormone measure or any hair-related outcome. Both groups saw a slight increase in total testosterone and a slight decrease in free testosterone over the 12 weeks, but these changes happened equally in both groups and had nothing to do with creatine. This was the first study to directly measure hair follicle health alongside creatine use, and it found no connection.
How Creatine Actually Works
Creatine’s benefits have nothing to do with hormones. It works through your cells’ energy system. Your muscles store creatine as phosphocreatine, which acts as a rapid fuel source for regenerating ATP, the molecule your cells burn for energy during short, intense efforts like sprinting or heavy lifting. By increasing these energy stores, creatine lets you perform more reps, recover faster between sets, and sustain higher training intensity.
Over time, this enhanced training capacity leads to greater gains in lean mass and strength. The muscle growth comes from doing more high-quality work in the gym, not from any shift in hormone levels. This is a key distinction: creatine is an energy supplement, not a hormonal one.
Long-term Safety Profile
The International Society of Sports Nutrition has stated that there is no compelling scientific evidence that short or long-term creatine use (up to 30 grams per day for five years) causes detrimental effects in otherwise healthy people. That position covers populations from children and adolescents to the elderly.
A 2025 study tracked 71 female football players through an entire 32-week competitive season while they took creatine (a standard loading phase of 20 grams per day for one week, followed by 5 grams per day). Researchers monitored 18 biochemical markers covering kidney function, liver function, and blood health. A few markers showed minor fluctuations mid-season, but all returned to baseline by the end and stayed within normal clinical ranges. No adverse effects on kidney or liver function were observed.
Differences Between Men and Women
Women naturally have 70 to 80% lower endogenous creatine stores than men and tend to consume less creatine through diet, which means they may stand to benefit more from supplementation. However, women also have roughly 10% higher resting levels of creatine already stored in their muscles, which could theoretically make them slightly less responsive to supplementation or require adjusted dosing.
Hormonal fluctuations across the menstrual cycle, pregnancy, and menopause all influence how the body synthesizes and uses creatine. Estrogen and progesterone affect the enzymes responsible for creatine production, and creatine kinase activity rises and falls in sync with estrogen levels. This means creatine supplementation may be particularly relevant during low-estrogen phases: the follicular phase of the menstrual cycle, postpartum, and post-menopause. Post-menopausal women have shown benefits in muscle size and function at higher creatine doses, with potential bone benefits when combined with resistance training.