Stabilizing the enzyme in fish odor syndrome L carnitine: Science Backed Benefits, Risks, and More Does Carnitine Cause Body Odor? Lume Deodorant Carnitine Injections: Everything You Should Know Frontiers A mixture of postbiotics tyndallized probiotics reduces trimethylamine (TMA) in trimethylaminuria models: Evidence from in vitro and in vivo studies 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.