If you are like a lot of people, you may have never heard of carnitine but this important nutrient is critical for our body's ability to optimally burn fat required for energy. L Carnitine Oral Bioavailability NOW l Carnitine Supplement Table 1 from The effects of L carnitine levels on Carnitine Deficiency: What Is It, Causes, Symptoms, and More Osmosis 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