What is L Carnitine, L Carnitine is an amino acid that plays a role in energy production and fat metabolism. Its found in foods like red meat, fish, and dairy, and also available as a supplement., L Carnitine Linus Pauling Institute Oregon State University Most oral L carnitine supplements are glorified flavored chemical waters., , Low bioavailability = very little of it actually gets picked up for use by the body., , So when companies sell $40$60 Low Bioavailability and High TMAO Production: Novel Insights Into Acetylcarnitine and Carnitine Metabolism KrimsDavis 2025 Molecular Nutrition & Food Research Wiley Online Library