Carnitine is an amino acid-like substance that synthesizes in the body from the amino acid lysine. It is present in many foods and high concentrations can be found in red meats, such as beef or lamb. In comparison, there is little to no carnitine in white meats and vegetables, so vegetarians maybe at risk of deficiency.
Carnitine supplements are available in several chemical forms- only the L-form of carnitine is biologically active (the D-form is inactive). Reduction of carnitine levels can occur from high fat diet, certain drugs (e.g. valproic acid antibiotics) or metabolic stress.
What does Carnitine do?
Carnitine is responsible for the transport of long chain fatty acids into mitochondria, where energy is produced within cells. It acts in synergy with coenzyme Q10 in the metabolism of fatty acids during energy production.
Carnitine is required for the healthy function of heart and skeletal muscle, since these tissues depend on fatty acid oxidation as a source of energy.