L-Carnitine

The amino acid L-carnitine is a cofactor required for the metabolism of fats and their subsequent transport into the mitochondria, where they undergo oxidation and produce energy.

Those prone to being deficient in L-carnitine and for whom supplementation might be advisable include individuals on dialysis and individuals who are HIV-positive. Supplementation with L-carnitine appears to be of benefit in supporting general wellbeing, appetite control, cardiovascular health, carbohydrate metabolism, reproductive health, and muscle health.

L-carnitine has also been shown to benefit athletic performance. For example, studies have shown improvements in running speed, decreased average oxygen consumption, heart rate, and lactic acid, and increased maximal oxygen uptake. Studies on high-repetition exercise found improved muscle recovery after L-carnitine supplementation.

L-carnitine is probably best known for its cardiac benefits. In the heart muscle, L-carnitine facilitates fatty acid use, and promotes rhythm, myocardial blood flow, and cardiac output. Carnitine also helps maintain blood lipid levels, with research showing support in maintaining already normal levels of total cholesterol, LDL cholesterol, lipoprotein(a) (associated with LDL cholesterol), and triglycerides