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 Frontiers The effect of L carnitine supplementation on lipid profile in adults: an umbrella meta analysis on interventional meta analyses The effect of (L)carnitine on weight loss in adults: a systematic review and metaanalysis of randomized controlled trials Pooyandjoo 2016 Obesity Reviews Wiley Online Library L CARNITINE 350 MG ( L CARNITINE ) 20 HARD GELATIN CAPSULES The adverse effects of long term l carnitine supplementation on liver and kidney function in rats L Liu, D M Zhang, M X Wang, C Y Fan, F Zhou, S J Wang, L D Kong, 2015