Carnitine, a short-chain nitrogen containing carboxylic acid, is found in meat and dairy foods. Carnitine aids in a shuttle process that makes long-chain, fatty-acid coenzyme A derivatives available for B-oxidation. Normal healthy adults have adequate carnitine stores and do not require dietary carnitine. However, neonates, chronically and critically ill patients with decreased muscle and liver carnitine store seem to benefit from carnitine supplementation to enhance their tolerance of metabolic stress.