Frontiers Gut Metabolite Trimethylamine N Oxide in Atherosclerosis: From Mechanism to Therapy Scientists make breakthrough in studying the enzyme involved in fish odor syndrome 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 Trimethylamine N Oxide From Gut Microbiota in Chronic Kidney Disease Patients: Focus on Diet Journal of Renal Nutrition Full article: Gutheart axis: emerging therapies targeting trimethylamine N oxide production