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 Life Extension, Creatine & Acetyl L Carnitine, Energy Plus Weight Loss Super Strength Supplements L Carnitine 500mg Amino Acid 2 Bottle CARSON LIFE Liquid L Carnitine, Green Tea, Boosts Energy, Metabolism, Dietary Supplement, 16 Fl Oz Walmart.com