Does creatine affect your sleep?

Creatine appears to improve how you experience your sleep. In a small study with 14 men, participants who took 20 grams of creatine per day for one week scored significantly better on a sleep quality scale than the placebo group. The effect was medium-sized and they also went to bed earlier. However, this is a single small study, so it should not be given too much weight.

What you feel yourself and what a device measures diverged in that same study. Objective measurement via a motion sensor worn on the wrist showed no difference whatsoever in how long it took to fall asleep, how efficiently participants slept, or how long they slept. Creatine may therefore change how your sleep feels without actually shifting the underlying sleep structure.

A second small study, involving 21 women who took 5 grams of creatine per day alongside strength training for six weeks, showed a slightly different picture. On training days, women in the creatine group slept significantly longer than women taking a placebo. On rest days and on the general sleep quality scale there was no difference. At most, this points to a recovery effect after exercise, not a broad sleep benefit.

There are also indications that creatine partially protects the brain against the effects of sleep deprivation. Creatine acts as a rapid energy reserve in the brain, which can be useful when you are short on sleep. A review article concludes that creatine supplementation can partially offset cognitive decline caused by sleep deprivation or ageing. The researchers themselves stress that the findings are preliminary and inconsistent.

As an additional effect, creatine also reduced muscle soreness after exercise. This could indirectly improve sleep, but that link has not been directly investigated in the available studies.