Trimethylaminuria (Fish Odor Syndrome or TMAU) L Carnitine L Tartrate Powder True Protein Does Carnitine Cause Body Odor? Lume Deodorant A recurring fishy odor could indicate a larger medical problem. Acetyl L Carnitine: Benefits and Side Effects Gene Food L carnitine supplements can cause a fishy odor in the breath, sweat, and urine. This is likely due to the formation of trimethylamine (TMA). TMA is also responsible for the pungent smell of