Creatine did not thin the hair of men who took it for 12 weeks
Over 12 weeks, 5g of creatine a day left resistance-trained men no different from placebo in hair density, follicle count, thickness or DHT.
What the study found
Twelve weeks of creatine left hair follicles unchanged
The first trial to actually look at hair looked at hair. Over 12 weeks, 5g of creatine a day left resistance-trained men no different from placebo in hair density, follicle count or thickness, nor in DHT, the testosterone-derived hormone blamed for shrinking follicles.
The caveat · 5g a day, not the 25g loading week
Twelve weeks is short against a process that takes years, so a slow thinning could begin after the trial ended. The 38 men who finished were all resistance-trained and aged 18 to 40, which leaves everyone else untested. And this was maintenance dosing at 5g a day; the older study that started the worry ran a 25g loading week first.
What we don't know
The creatine hair worry and the hair trial measured different things: a hormone shift during a week of 25g a day, and hair itself after twelve weeks of 5g a day, which showed nothing. Both may be right.