What is Trimethylaminuria?

Trimethylaminuria, also known as fish odor syndrome or malodor syndrome is a metabolic disorder caused by non-conversion tri methyl amine in the body into tri methylamine oxide. It is a chemical produced in the bowel by the digestive system while digesting the food consumed. When tri methyl amine content in the food consumed is not converted into its oxide, it comes out of the body through sweat, urine, reproductive fluids or breathe emitting a fish odor or strong body odor.

Who is at high risk?


This syndrome is more common in women than men. Women, particularly those around the monthly period times (before, during or after the period) and after menopause are more prone to this disorder. Consumption of oral contraceptives is also a factor that cause the syndrome.


The disorder is classified as primary and secondary trimethylaminuria.

  • The inherited autosomal genetic disorder is the primary form which is a rare occurrence. It may become noticeable in childhood itself or may be on adulthood. It can start at any age in life.
  • Secondary form is due to inhibition of breaking tri methyl amine into tri methyl amine oxide by the enzymes produced in the liver particularly due to larger doses of dietary precursors (choline, lecithin, trimethylamine N-oxide) containing tri methyl amine.

It is a rarely reported disorder since people with mild body odor do not consult a doctor or attempt a diagnosis. Only where the odor becomes too strong causes social stigma, the person affected venture to diagnose and seek remedy to cure the disorder.

The fishy odor may not be of the same intensity at all times and may vary based on the metabolism and food preferences.


The disorder can be diagnosed just based on the smell. Since not everybody can identify the smell of tri methylamine from other odors laboratory test is conducted on the urine sample in order to confirm that the bad odor is only on account of non-conversion of tri methylamine.

A genetic test can also be conducted to find out whether the disorder is primary or secondary.

Impact of the disorder

Barring the foul odor there is no adverse effect on other medical conditions of the person affected by this disorder. However it has social implications. Those affected may not smell the unpleasant odor themselves but people around them might notice it and inform them or even avoid them. They may not be able to freely socialize or move with others. People may try to avoid those having such body odor and such avoidance over a period of time may even lead to mental depression. Hence it is very important to treat the disorder in order to significantly reduce the order even if it cannot be totally cured.

There is no cure for the disorder but can be treated to reduce the symptom.

Tips to reduce symptom


  • People affected by this disorder can reduce the fish odor by avoiding food that has good amount of tri methylamine or its precursors. Some such food items they need to avoid are:
  1. Milk from wheat fed cow
  2. Peas, beans, peanuts and soya products
  3. Cabbage, cauliflower, brussels sprout and broccoli
  4. Eggs, liver, kidney
  5. Supplements of fish oil with lecithin
  • It can be further treated by taking antibiotics to reduce the bacteria in the gut. Laxatives may also reduce the production of tri methylamine in the intestine.
  • Soaps which are slightly acidic with moderate pH can be used in order to reduce the volatility of the chemical on the body which reduces the odor.
  • Exercising extensively which produce more sweat than normal times can be avoided. This will only help the reduction of body odor but the unwanted chemical has to otherwise come through urine for which supplements may be taken appropriately.
  • Medicines can be taken to reduce the concentration of tri methylamine in the urine.
  • Consumption of charcoal for about two weeks with a dosage of 750mg twice a day is recommended as a remedy.
  • Copper chlorophyllin thrice a day for about twenty days and riboflavin supplements regularly are also some suggested remedy for the disorder.

It should be ensured that medicines or dietary supplements are taken only with a doctor’s advice and self-medication must be avoided. If taken without medical consultation unintended consequences like nutrition deficiency can occur.

For example choline is required for development of the brain and nervous system of the fetus and infants. Hence pregnant women who suffer due to trimethylaminuria must take any medicine or supplement only after obtaining advice from the doctor taking into account other medical conditions.

It has been established that most of the people who are affected by the syndrome can totally cure the same by adopting various remedial measures both preventive and curative.

Kripa Sivasubramanian, MBA, earned her Master’s degree in Business. After a long stint in the Technology sector, she took up courses in natural medicine and yoga. Ms. Kripa is certified in Ayurvedic yoga for Dosha. She is also certified by Stanford University School of Medicine in Introduction to Food and Health.