Comprehensive review of the expanding roles of the carnitine pool in metabolic physiology: beyond fatty acid oxidation Journal of Translational Medicine Springer Nature Link 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 L Carnitine Injection Levocarnitine IV L Carnitine The Wonder Fat Loss Miracle or Just Marketing Hype? FIT Asia Advancing Fitness Education