Metabolic Optimizer L Carnitine supports cellular energy production. L Carnitine For Weight Loss: 10 Key Benefits, Diet Plan, Dosage 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 Nutra BioGenesis L Carnitine L Carnitine Supplement Gluten Free, Vegan, Non GMO 60 Capsules L carnitine known as the energy nutrients, provides massive benefits to your heart and works best with Alpha Lipoic Acid.