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 Acetyl L Carnitine 500mg Amino Acid Supplement Nature's Best What is Carnitine? L Carnitine Benefits, Uses, Dosage, Foods, Side Effects Dr. Axe L Carnitine plays an important role in the larger metabolism equation: helping your body use fat efficiently as fuel. Learn more about the science on this week's post on The Wellness Edit.