L-glutamine, sometimes called simply glutamine, is an amino acid that plays a a key role in maintaining health. It is not among the 9 essential amino acids that must be obtained from food, but some experts consider that it could be added to the list chosen for its importance for the functioning of the immune system and metabolism.

Some authors also propose glutamine as a nutrient that promotes weight loss. It is true that there are studies in this sense. One of them, carried out at the University of Tehran and published in the journal Nutrients, shows that the intake of 30 g of glutamine powder per day reduces body fat, especially belly fat, and reduces the risk of heart disease. The dose used is well above daily needs.

Other research, carried out separately at the Brazilian University of Campinas and at the Sapienza University of Rome, confirms that glutamine is capable of reduce waist circumference in overweight or obese people. Very high doses were also used in both studies.

However, other scientific works have not been able to corroborate the results, perhaps because smaller quantities were used.

How can glutamine promote weight loss?

Scientists who have investigated the properties of glutamine explain that it can act on body weight through several mechanisms:

• Can modify the composition of the intestinal microbiota, the community of beneficial bacteria that inhabit the digestive system. As is known, the microbiota can influence the functioning of the metabolism and promote weight loss or gain.
• Glutamine can reduce inflammation, which is linked to many chronic conditions, including obesity.
• Can increase insulin sensitivity in fatty tissue, which allows it to be transformed into energy.

How can you get more glutamine?

The body is capable of synthesizing glutamine from other amino acids provided by food. One of its main destinations is muscle tissue. It is also found in blood plasma, spinal cord and cerebrospinal fluid.

One of its functions is «cleanse» of lactic acid and ammonia, a metabolic waste that can be toxic, both to the muscles and the brain. In fact, it is a popular supplement among athletes because it promotes the repair of muscle tissue and allows you to train with more intensity (because it delays the appearance of soreness).

Glutamine participates in acid-base balance of the organism. It does this, for example, by promoting the elimination of acid in the kidneys. It is also involved in the production of new skin cells, hair and immune cells. It is also one of the precursor amino acids of glutathione, one of the most powerful endogenous antioxidants (produced by the body itself).

What foods is glutamine found in?

Glutamine is found naturally in a variety of foods, including tofu, legumes, nuts, spinach, eggs and, above all, dairy products.

It is also available in supplement form, including powders and capsules, which are considered safe when the dose does not exceed 14 g daily, although up to 30 g has been used in studies. The most frequently recommended doses range between 500 mg and 3 g daily, which are taken between meals.

Although it is a safe supplement, if you suffer from any disorder or take medication it is recommended consult with the doctor in case there are contraindications.

In any case, we cannot expect that a nutritional supplement, be it glutamine or any other, will be the only and quick solution to control weight. Obesity and overweight are complex problems that require comprehensive treatment that includes changes in diet, activity and rest routines, as well as stress control and emotional balance.

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