As L-Carnitine Tartrate Important Cofactor for Energy Production from Fats Vegan 500 Milligrams Veggie Caps Dietary Supplement Suitable for Vegetarians/vegans L-Carnitine is an amino acid found in high concentrations in heart and liver tissues where, inside the cells (mitochondria), L-Carnitine helps transforms fats into energy (i.e., energy). L-Carnitine also facilitates the metabolism of carbohydrates and enhances ATP production. L-Carnitine works synergistically with Co-Q10 an antioxidant and ATP production cofactor that is found in the inner membrane of the mitochondria.