Carnitine: Genetic Variants Affecting Mitochondrial Energy and Health What is L Carnitine, L Carnitine is an amino acid that plays a role in energy production and fat metabolism. Its found in foods like red meat, fish, and dairy, and also available as a supplement., Pharmacokinetics of L Carnitine Clinical Pharmacokinetics Springer Nature Link L Carnitine Oral Bioavailability NOW l Carnitine Supplement Carnitine: the claims and why it may not work