Does L carnitine cause fishy body odor? Surprising Truth and Solutions Tonum Trimethylaminuria: Definition, symptoms, and more 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. Does Carnitine Cause Body Odor? Lume Deodorant 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