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 creatine powder for about a week—first a lot, then a little—can boost the amount of creatine in your muscles by over 13%, which helps your muscles store more energy.

Taking creatine supplements might help older people (66–76) remember things better, maybe because it gives their brain more energy—but it doesn’t seem to help younger people (11–31) at all.

Taking creatine monohydrate every day for up to five years, even at high doses, doesn’t seem to harm your kidneys, liver, or blood in healthy people or those with brain-related diseases like Parkinson’s or ALS.

Taking 20 grams of creatine powder a day for 5 days can make you gain about 1.2 kg in weight and help your muscles store more energy, at least in people whose bodies respond well to creatine.

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.