Taking creatine might help your brain work better when you're tired or under mental stress, because it can boost a special energy molecule in your brain.

Taking creatine supplements might help your muscles and brain store more energy, which could keep your cells from running out of power, help build muscle, stop muscle from breaking down, and keep your cell walls stable.

Taking creatine supplements can slightly boost the amount of creatine in your brain—by about 3 to 10%—but not as much as it boosts your muscles, probably because your brain is harder to reach with supplements and makes some creatine on its own.

Taking 0.2 grams of creatine monohydrate per kilogram of body weight as a single oral dose can reduce the decline in cognitive functions such as logical reasoning, numerical processing, language speed, and attention during 21 hours without sleep in healthy young adults.

During sleep deprivation, taking more creatine (0.35 g/kg) leads to slightly better cognitive performance than taking less (0.2 g/kg), but the benefit does not increase beyond a certain dose, suggesting the brain reaches a limit in how much creatine it can use under these conditions.

After 21 hours without sleep, taking 0.35 grams of creatine per kilogram of body weight increases the ratio of creatine to N-acetyl-aspartate in a specific region of the brain by up to 6.1%, suggesting that sleep deprivation may temporarily allow more creatine to enter brain cells than under normal conditions.