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Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Last full review/revision Jul 2020| Content last modified Jul 2020

Creatine is an amino acid made in the liver and stored in muscles. When combined with phosphate, it is a readily available source of energy in the body. In the diet, creatine is found in milk, red meat, and some fish.

(See also Overview of Dietary Supplements.)

Medicinal claims

People take supplements of creatine to improve physical or athletic performance and to decrease muscle fatigue. Some studies indicate that creatine can increase the amount of work performed with a short maximal effort (for example, in sprinting).

Possible side effects

Creatine supplements may cause weight gain and may elevate levels of creatine in the urine and blood and cause kidney dysfunction. Minor stomach upset, dehydration, and muscle cramps occur occasionally. People who have a history of kidney dysfunction should avoid creatine supplements.

More Information about Creatine

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • National Institutes of Health (NIH), National Center for Complementary and Integrative Health: Dietary Supplements Marketed for Weight Loss, Bodybuilding, and Sexual Enhancement: What the Science Says

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