Comparison of L carnitine levels in different studied groups. Download Table 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. 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 Serum L Carnitine Levels Are Associated With First Stroke in Chinese Adults With Hypertension Stroke Lypo Spheric Acetyl L Carnitine