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 Medium chain fatty acid oxidation is independent of l carnitine in liver and kidney but not in heart and skeletal muscle American Journal of Physiology Gastrointestinal and Liver Physiology American Physiological Society Combined protective effects of oligo fucoidan, fucoxanthin, and L carnitine on the kidneys of chronic kidney disease mice ScienceDirect The effects of L carnitine on renal function and gene expression of caspase 9 and Bcl 2 in monosodium glutamateinduced rats BMC Nephrology Springer Nature Link