L Carnitine Did you know L carnitine, a vital amino acid, is naturally produced by your body and found in various foods? While acetyl L carnitine (ALCAR) can be a beneficial supplement for some, most people get Potential effects of l Carnitine supplementation on different Download Scientific Diagram 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 Benefits: A Complete Research Based Guide L Carnitine Linus Pauling Institute Oregon State University