Genes can be blamed for bad body odor, a new study shows.

Scientists at the Monell Chemical Senses Center in Philadelphia tested 353 people who had bad body odor despite having good hygiene, and 188 of them tested positive for trimethylaminuria (TMAU).

TMAU is a metabolic disorder that can be genetically inherited. It impedes enzymes from metabolizing or transforming trimethylamine (TMA), which is associated with foods that contain choline. Part of patient-testing included a choline challenge.

Choline can be found in foods such as eggs, milk, chocolate, Brussels sprouts, sun-dried tomatoes, some legumes, beef liver, chicken liver, salmon, wheat germ and cauliflower.

Health care professionals must arrive at a correct diagnosis to suggest appropriate treatment, lead author and Monell sensory psychologist Paul M. Wise said. This research raises awareness of both the disease and also the proper methods of diagnosis and treatment.

TMAU was popularly known as fishy odor syndrome, but Monell scientists say that a fishy odor is not always the case, as it can cause a person to emit various levels of bad-smelling odors.

Although the scientific and popular literature typically describes TMAU sufferers as smelling fishy, our sensory exams demonstrated this not to be so, study author and Monell analytical organic chemist George Preti said. The odors are diverse and only after a choline challenge do the most severe cases have a fish-like odor.

The study was published in the American Journal of Medicine.