L Carnitine: Benefits, Uses, and Side Effects Lifespan Research Institute Does L carnitine cause fishy body odor? Surprising Truth and Solutions Tonum The main reason why people may experience a fishy taste, smell, or burp when taking #fishoil is that they are not taking a high quality #fishoilsupplement. When it comes to manufacturing Optimizing endurance performance in elite swimmers: effects of L carnitine supplementation and hydration strategies Applied Water Science Springer Nature Link 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. 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.