Acetyl-L-Carnitine is an amino acid that acts as a vitamin-like compound, responsible for the transport of long-chain fatty acids into the energy producing mitochondria inside cells. Since the carrier molecule for fatty acids, acyl-CoA, cannot penetrate the cell membrane of the mitochondria without carnitine, a deficiency in carnitine results in decreased fatty acid concentrations in the mitochondria, and as a result, reduced energy production.
L-Carnitine is only found in animal food sources such as meat, poultry, and dairy products. L-Carnitine can be made in the human body, although premature infants and some adults do not make sufficient amounts. L-Carnitine is a popular supplement for heart health, liver health, and weight loss. Studies generally use dosages ranging from 2 or more grams per day.