L carnitine is primarily synthesized in the liver from the amino acids lysine and methionine through a series of four enzymatic reactions, with the liver and kidneys converting the precursor butyrobetaine into active Congestive Heart Failure: Supplements for Heart Health Levocarnitine, commonly known as L Carnitine, is a naturally occurring compound that the body produces from the amino acids lysine and methionine. It plays a critical role in energy production by transporting fatty Risks and benefits of carnitine supplementation in diabetes. Semantic Scholar