Meet L Carnitine a naturally occurring amino acid that plays a key role in helping the body convert fat into usable energy. It works by transporting fatty acids into your cells to Been taking these for a month with no noticeable effect : r Biohackers 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 Did You Know? Some people report a fishy smell after supplementing with L carnitine. This happens because certain gut bacteria convert carnitine to trimethylamine, a malodorous compound found in rotting fish.