When a 12 month old boy in Portugal developed an unexpected and persistent smell similar to rotting fish, his parents were unsettled. The child appeared healthy, showed no signs of infection, and behaved normally. Does Carnitine Cause Body Odor? Lume Deodorant La L carnitina es el suplemento estrella para perder peso: esto es lo que nos dice la ciencia sobre sus efectos Trimethylaminuria, or fish odour syndrome is an uncommon condition that causes an unpleasant, fishy smell. The body is unable to turn a strong smelling chemical called trimethylamine produced in the gut when