L Carnitine and Sleep: Does It Affect Rest or Sleep Quality? How Much L Carnitine Per Day: Expert Guide The Science of Good Health L CARNITINE increases muscle mass, reduces fat mass. Bangkok Hospital Headquarter 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 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.