L Carnitine Benefits for Fat Burning and How to Use ICONFIT Carnitine: the claims and why it may not work L carnitine is a naturally occurring amino acid structure that is made in the human brain, liver, and kidneys. L carnitine plays a critical role in energy production, as it converts fat into energy. The Role of l Carnitine in Mitochondria, Prevention of Metabolic Inflexibility and Disease Initiation L Carnitine and Weight Loss: Does This Fat Burner Really Work? Health Guide