Now Foods L Carnitine Capsules L Carnitine, 500 mg. MAKEUP Carnitine: the claims and why it may not work L Carnitine Linus Pauling Institute Oregon State University What even is carnitine?? Carnitine is a "conditionally" essential amino acid that becomes essential during pregnancy. What does this mean? You must get carnitine through food! The best sources are red Acetyl L Carnitine Moselle Natural Health Amino Acids for Super Humans, Part IV Purported Ergogenics (2 3): L Carnitine, ALCAR, LCLT, GPLC & Co.