Does L carnitine cause fishy body odor? Surprising Truth and Solutions Tonum L Carnitine for Weight Loss: How It Works, Dosage & Best Supplement Zeelab Pharmacy 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. 7 Medical Conditions That Cause Bad Body Odor HealthcareOnTime Body odour isnt just about deodorants or perfumes it starts from within. The food you eat plays a powerful role in balancing your bodys natural scent, keeping you fresh, confident and healthy. Try 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.