Fish Odor Carnitine TikTok Does Carnitine Cause Body Odor? Lume Deodorant L Carnitine Benefits for Fat Burning and How to Use ICONFIT 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. Revisiting the Role of Carnitine in Heart Disease Through the Lens of the Gut Microbiota