L Carnitine Benefits, Uses, Dosage, Foods, Side Effects Dr. Axe What Is Carnitine and Why Is It Important? The Amino Company Fitprosupps Liquid L Carnitine What is L Carnitine? L Carnitine is a naturally occurring amino acid derivative that the human body can synthesize itself. It is mainly found in red meat and dairy products. [1] Core Benefits of L Carnitine contents in foods (modified from [70]). Download Scientific Diagram