Although plausible, it seems unlikely that supplementing with creatine causes hair loss.
By binding to androgen receptors in susceptible hair follicles, dihydrotestosterone (DHT; a testosterone metabolite) can cause hair follicles to shrink, ultimately leading to hair loss.[1][2] That said, whether a given hair is more or less likely to fall depends on its location (in male-pattern hair loss, the crown and hairline thin first) and the person’s genetic predisposition to hair loss.[3][4]
A proposed mechanism behind creatine’s effect on testosterone
The idea that supplemental creatine could be linked to hair loss largely originates from the findings of a 2009 randomized controlled trial.[5] In this trial, college-aged male rugby players who took creatine monohydrate for 3 weeks experienced a 41% increase in their blood levels of DHT. The baseline DHT concentration was 0.98 nmol/L and the concentration after 3 weeks was 1.26 nmol/L, with both values being well within the normal range.
To date, this has been the only trial testing creatine’s effects on DHT. However, 12 other trials have tested creatine’s effects on testosterone. Of these, only two trials (lasting 6 and 7 days) have reported increases in testosterone levels,[6] [7] while the remaining 10 trials (which ranged in duration from 6 days to 12 weeks) found no effect.[8][9][10][5][11][12][13][14][15][16] Importantly, 5 of these trials specifically tested creatine’s effects on free testosterone, the form of testosterone that gets converted to DHT, and found no significant increases.[8][11][13][9][15]
Lastly, and perhaps most importantly, the effect of supplemental creatine on hair loss hasn’t been directly studied, so all we can do is make educated guesses.
To sum up: (i) Only one trial has reported an increase in DHT levels with supplemental creatine; (ii) although DHT levels increased, they stayed well within the normal range; (iii) no other trials have looked at the effect of supplementing with creatine on DHT levels, but 10 of the 12 trials looking at the effect of supplemental creatine on testosterone, five of which also looked at free testosterone, reported no effect; and (iv) the effect of supplemental creatine on hair loss hasn’t been directly studied.
With the above in mind, we can conclude that, although plausible, it seems unlikely that supplementing with creatine causes hair loss.