Are L Carnitine and L Carnosine the Same? Anti Aging Systems If you are like a lot of people, you may have never heard of carnitine but this important nutrient is critical for our body's ability to optimally burn fat required for energy. What Is L Carnitine? L Carnitine Benefits, Dosage & When To take? MYPROTEIN L CARNITINE increases muscle mass, reduces fat mass. Bangkok Hospital Headquarter Early research into L carnitine was often cited as underwhelming, showing negligible changes in muscle carnitine content and fat loss outcomes. However, these findings may have been limited by a short study window