Glutathione is a compound naturally present in animal and plant cells, but also in certain bacteria. It is a powerful antioxidant, capable of preventing cell damage caused by free radicals or any other species reactive to oxygen; it thus helps to limit the appearance of many pathologies linked to oxidative stress.
Free radicals are by-products of biochemical reactions that take place in our body, in other words, they are unavoidable. Our body needs oxygen, but certain mechanisms sometimes split oxygen molecules into two single atoms, with an unpaired electron. These lone electrons then tend to search for another electron in the organism, so as to form a stable pair again; they attack the cells to snatch this electron from them.
To neutralize these free radicals, a sufficient intake of antioxidants – most of which come from our diet – is therefore essential. Antioxidants encompass several types of substances, such as carotenoids, polyphenols, zinc, selenium, vitamins (A, C, D and E). “Colored” fruits and vegetables, as well as tea, coffee, cocoa, and certain spices and aromatic herbs, are renowned for their strong antioxidant power. Less known, glutathione is nevertheless considered a powerful scavenger of free radicals and reactive oxygen species.
Glutathione is a tripeptide naturally synthesized by our body from three amino acids:glutamic acid, glycine and cysteine. It is found in high concentrations in virtually all cells of the body. This natural antioxidant is also found in animals, plants, fungi and some bacteria. It exists in two forms:a reduced form (GSH) and an oxidized form (GSSG).
The reduced form of glutathione represents approximately 98% of the body's total glutathione level:it is this form that has the potential to prevent reactive oxygen species from attacking cells by neutralizing them. In addition to its ability to fight against oxidative stress, it also contributes to other defense processes:it participates in particular in the transformation of the oxidized form of ascorbic acid into vitamin C and stimulates its antioxidant power, just as it contributes to maintain vitamin E in its reduced (therefore active) state.
Glutathione also participates in several metabolic processes, such as the biosynthesis of leukotrienes and prostaglandins (involved in certain inflammatory reactions and vasodilation). It also plays an essential role in the metabolism of medicinal substances. Finally, it promotes the elimination of waste and toxic compounds via bile and urine. A recent study even suggested that glutathione deficiency was associated with severe forms of COVID-19.
But with age, especially from the age of 50, the blood level of glutathione drops sharply. In addition, the synthesis of free radicals can be favored by certain external factors (pollution, tobacco, UV radiation, stress, etc.), which deplete our reserves of this antioxidant even more quickly. Ultimately, excess free radicals can lead to premature aging of cells and contribute to the appearance of certain pathologies (cancers, cardiovascular diseases and degenerative diseases).
Glutathione is one of the antioxidants that is not found in food (or in very small quantities) - it is also very poorly absorbed in this way. On the other hand, certain foods contain the three amino acids necessary for its synthesis. We can therefore find glutamic acid, cysteine and glycine in mushrooms, asparagus, cabbage, spinach, grapefruit, oranges, raspberries, or even avocado.
It is also possible to find the benefits of glutathione in the form of dietary supplements. These are particularly recommended for the elderly, as well as for those whose lifestyle is conducive to high production of free radicals (chronic stress, urban pollution, etc.). Note that the simultaneous intake of vitamin C increases its absorption and its effects. Certain trace elements are also known to enhance its action:these are glutamine, zinc, copper, manganese, iron or even selenium.
In general, to limit the production of free radicals, it is necessary to adopt a healthy lifestyle, which consists of moderate exposure to the sun, avoiding polluted environments and banning tobacco. At the same time, a varied and balanced diet, rich in fruits and vegetables, will help maintain a satisfactory level of antioxidants; conversely, know that saturated fatty acids and alcohol are major triggers of free radicals.
