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Trimethylaminuria, the disturbance that causes the smell … of rotten fish

Seated woman isolated for trimethylaminuria

Trimethylaminuria is a metabolic disorder that mainly affects women. Let’s find out what causes it and how it can be resolved.

Trimethylaminuria is a disease that affects women’s metabolism and causes an unpleasant smell of rotten fish . Most of the time to emanate this stench are urine, sweat and breath and the incidence increases in women due to the greater presence of hormones such as estrogen and progesterone. Generally at the origin of trimethylaminuria there may be hormonal and metabolic dysfunctions. The best known variant of this disease is genetic and occurs mainly during weaning . Even if the bad smell is not constant it can increase if you consume certain foods or go through specific phases of life and growth. To date, however, there is no cure, even if this disorder can be treated by taking care of your diet and lifestyle. But let’s see all there is to know about trimethylaminuria.

Trimethylaminuria: what it is

As we have anticipated, trimethylaminuria, normally abbreviated as TMAU, is a disturbance of the female metabolism , which causes the smell of rotten fish. At the root of this dysfunction we can find two main causes.

Isolated girl in school
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The first is linked to mutations and genetic changes , specifically those affecting the monooxygenase-3 gene, responsible for the production of flavin. These changes can cause the alteration of the enzyme responsible for the conversion of trimethylamine amine, a foul-smelling compound, to N-oxidized trimethylamine.

In practice, trimethylaminuria causes an accumulation of this compound in the body, precisely because of the lack of processing, which is then expelled through urine, sweat or breath . In other cases, this unpleasant disturbance can be caused by an excessive elimination of trimethylamine, caused in most cases by pathologies of the liver, intestine or hormonal changes.

Trimethylaminuria: symptoms

Although trimethylaminuria causes an unpleasant rotten fish smell, no other problems have been found related to this pathology. As we have already said, however, the emission of odor can increase the certain phases of life , such as during puberty, the menstrual cycle or after a particularly excessive physical effort.

In other cases, trimethylaminuria is linked to the consumption of specific foods that contain compounds such as lecithin, choline or cartinine. The most serious consequence of trimethylaminuria is certainly on a psychological level. In fact, the vast majority of patients live in solitude or social isolation precisely because of the disease and, very often, they can suffer from anxiety and depression.

Younger patients have also been found to drop out of school and maintaining stable relationships, both work and love, is extremely difficult. All this only aggravates the condition of those suffering from trimethylaminuria.

How to cure trimethylaminuria

Most of the time trimethylaminuria is diagnosed by measuring the quantities of trimethylamine present in the urine. The results are then crossed with specific genetic tests performed to understand if the cause of the pathology is hereditary. In any case, however, an effective cure has not yet been found to solve this pathology.

However, it is possible to treat trimethylaminuria by changing food habits and diet, especially if you want to reduce the intensity of the smell of fish. The advice is to often take showers with specific pH soaps or follow a real ad hoc diet to limit foods containing trimethylamine precursors.

The foods to be strictly avoided are fish, peas, eggs, liver or seafood. In any case, given the psychological consequences, the support of a specialist can be of great help.

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