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. Didn't another study show carnitine was good for the heart? L Carnitine is Underrated. New Meta Review Reminds Us Why. Why should I take L Carnitine? L Carnitine doesnt magically burn fat, it helps your body use fat as energy. Combine it with training and consistency, and youll feel the difference @Marybosch shows us how L Carnitine will boost