Does umami taste ingredients make you fat?

Obesity and overweight have become concerning lately, since there has been an increase in individuals with these types of illnesses, which may be associated with others such as cardiovascular diseases, type II diabetes, insulin resistance, and dyslipidemias, which are typical characteristics of the so-called “Metabolic Syndrome.”
Different theories to discover what is really the cause of obesity and/or overweight have been discussed in congresses and also in articles published in renowned scientific journals.

Some studies carried out in neonatal animals verified that glutamate, a non-essential amino acid, i.e., produced by the body, when administered in high doses (4.0 mg/g of body weight) by intraperitoneal route*, can damage the arcuate nucleus of the hypothalamus, a brain region that responds to leptin signaling cascade, which acts by inhibiting the synthesis and/or secretion of neurotransmitters that regulate appetite. The hypothesis suggests that if this damage occurs, leptin cannot act, and then there is a deregulation in signal transmission, causing an increase in the animals’ appetite and, consequently, weight gain (FAINTUCH, 2011; MALULY et al., 2013).

However, as clarified, the studies revealed that this fact occurs if there is an injection of high amounts of glutamate in the body of neonatal rats or mice, which exceed the normal production of this amino acid in the animal’s body. It would also be very dangerous to inject high amounts of any other substance into the body, such as salt, sugar, or water, or another essential or non-essential amino acid, for example.

Glutamate intake in daily life:

The consumption of glutamate through foods does not exceed more than 12 grams per day, when consumed naturally or through foods containing monosodium glutamate. This amino acid, when ingested, is used by intestinal cells to generate energy, therefore, what reaches the bloodstream is a minimal amount (up to 5%), which, when compared to endogenous production, has no significance and would not cause any type of damage. For this reason, it is considered safe for human consumption (MALULY et al., 2013).

As for the umami sensation on the tongue, we can say that it is a pleasant sensation like any other taste, and high amounts can compromise the flavor of preparations. In the case of adding monosodium glutamate to foods, it is recommended to use a maximum of 1.0% of the total amount of the preparation, so that it promotes umami without interfering with the food’s own flavor.

Another novelty is in research regarding the consumption of umami substances and satiety. Some researchers verified that a glutamate diet may help in promoting satiety. This may occur due to the presence of receptors for glutamate and nucleotides in the stomach and the activation of the vagus nerve, which transmits satiety information to the brain. However, the actual mechanisms are still being investigated (MASIC et al., 2014).

What is already very clear is that the most different studies have shown that weight gain is directly associated with genetic factors, poor diet, and lack of physical activities. The fault is not in the food, since each individual has their own choice, in addition to other cultural, social, physiological, genetic, and psychological factors.