Understanding the Benefits of L Carnitine for PCOS Management L carnitine is a naturally occurring amino acid structure that is made in the human brain, liver, and kidneys. L carnitine plays a critical role in energy production, as it converts fat into energy. L Carnitine has become one of our top 5 sellers the last few years and when you review the research, you can see why. L carnitine is a supplement probably more well known if L Carnitine Health & Balance Vitamins (USA) Health & Balance Vitamins PCOS Nutrition Center L Carnitine (120 Capsules)