L-carnitine is an amino acid derivative found in almost all cells of the human body where it is involved in the production of adenosine triphosphate (ATP), a form of biological energy. L-carnitine can be synthesized in the liver and kidneys from the essential amino acids L-lysine and L-methionine 1. It can also be consumed in foods of animal origin, such as lamb or beef, or as a dietary supplement. L-carnitine is approved for use as a food additive by the U.S. Food and Drug Administration (FDA) 2.


  1. PDR for Nutritional Supplements. Montvale, NJ: Physicians’ Desk Reference, Inc, 2008.
  2. Food and Drug Administration. EAFUS: A Food Additive Database. 10-17-2008. 12-4-2008.