Those who have TMAU are plagued by extreme body odor: Their urine, breath, and sweat are laced with a thick scent akin to that of rotting eggs, garbage, or stale fish, and it's completely impossible to control with bathing, deodorant, or other forms of personal hygiene.

Riboflavin (vitamin B2) administration has been associated with reduction of TMA excretion in some TMAU patients (unpublished observations) presumed to be due to increased FMO3 activity with riboflavin acting as a co-factor.

As excess trimethylamine is released in a person's sweat, urine, and breath, it causes the odor characteristic of trimethylaminuria. Researchers believe that stress and diet also play a role in triggering symptoms.