Glutathione – what does it do and is it worth supplementing?

Cell protection, detoxification, oxygen transport – these are just some of the areas for which the glutathione molecule in the human body is responsible. Considered the strongest antioxidant in the body, glutathione is a substance that remains largely unknown to the general public. What is worth knowing about one of the most important defenders of the human body, and how can we ensure a high supply of it in our daily diet?

Glutathione – what exactly is it?

L-Glutathione, also known as ‘glutathione’ for short, is a natural endogenous substance found in virtually all human cells. The body needs three components to produce the substance itself: glutamic acid, cysteine and glycine. From a chemical point of view, this trio of amino acids is why glutathione is also called a ‘tripeptide’.

Essentially, all cells in the body have the built-in ability to produce glutathione. However, the largest amounts are produced in the liver, where it plays an extremely important role. The highest concentrations of l-glutathione are found, as mentioned earlier, in our liver, as well as in our blood and immune cells.

Reduced glutathione (GSH) and oxidised glutathione (GSSG) – what is worth knowing about them?

Glutathione occurs in the body in both reduced form as GSH and in oxidised form as GSSG (glutathione disulphide). The quantitative ratio of both forms in the cell determines the state of redox reactions, i.e. the type of chemical reactions in which one reagent transfers electrons to another reagent in the cell.

This form of reaction determines whether the glutathione in our body will actually be a biologically active molecule. Reduced glutathione (GSH) is the only active product known to us today that, in its reduced form, can fight free radicals by giving them the electrons it contains. GSH is then oxidised to GSSG. Glutathione disulphide itself cannot act as an antioxidant and must be converted back into active, ‘reduced’ glutathione.

In order to recover oxidised glutathione, it is important that all the body's systems work together perfectly, are efficient and healthy. If this is not the case, a dangerous glutathione deficiency may occur in the body.

Foods rich in glutathione – which ones are they?

We already know that the most important form of glutathione in our body is GSH. So, is it possible to obtain GSH from food? As it turns out, yes. For most products containing GSH, the following rule applies: the fresher the food, the more glutathione it contains. However, some products, such as asparagus and carrots, contain more glutathione when cooked than when raw.

So, which foods are rich in glutathione? Glutathione occurs naturally in, among others:

• Watermelons

• Avocados

• Broccoli

• Pumpkin

• Cauliflower

• Chicken

• Carrots

• Beef

• Peanuts

• Peppers

• Parsley

• Oranges

• Tomatoes

• Asparagus

• Spinach

• Liver

• Potatoes

To meet the demand for reduced glutathione through diet, it would be necessary to consume large amounts of the above-mentioned products. In addition, the glutathione content in fresh food may decrease significantly due to transport or storage time, as GSH is susceptible to rapid oxidation reactions that convert it into inactive GSSG. In this case, additional dietary supplements or a well-designed nutrition plan may be helpful.

Glutathione levels in the body and oxidative stress – how to test them?

The human body is capable of producing glutathione on its own, but in everyday life it is quickly depleted, e.g. under the influence of psychological and environmental stressors. An unbalanced or deficient diet can lead to a lack of glutathione building blocks and, consequently, to glutathione deficiency. In addition, the body's ability to synthesise glutathione decreases with age, so it is important to regularly test glutathione levels in the body and consider glutathione supplementation. How can this be done?

If we want to measure our own glutathione levels, we can do so by having a blood test (full blood count). During the test, several values are recorded, because it is not only the glutathione level itself that is important, but also the ratio of reduced glutathione to oxidised glutathione. The proportion of reduced glutathione should be between 80 and 90% of total glutathione.

This ratio is a good parameter for determining the overall detoxification capacity of cells and the current oxidative load. If the proportion of reduced glutathione decreases, it may be a sign of severe oxidative stress, reduced detoxification capacity or a hidden medical condition.

Glutathione deficiency – what are the symptoms?

L-glutathione deficiency in the body is associated not only with serious diseases, which it usually causes, but also with certain symptoms that can hinder our daily functioning. If there is no longer sufficient amounts of reduced, i.e. active, glutathione in the body, cellular metabolism and the immune system are significantly degraded and weakened. Glutathione deficiency manifests itself in the following ways:

• Chronic mental and physical fatigue and exhaustion,

• Frequent or prolonged infections caused by viruses, bacteria and fungi,

• Increased risk of inflammation,

• Prolonged recovery time after infections,

• Loss of physical and mental immunity manifested, among other things, by a lack of psychomotor skills, memory and concentration problems,

• Depressive episodes and mood swings.

Even if the demand for glutathione cannot be met by diet alone, it is recommended to support glutathione metabolism through a healthy lifestyle. Limiting the use of stimulants such as alcohol and cigarettes can help restore the body's original levels of reduced glutathione.

L-Glutathione – how does it help the body?

L-glutathione is involved in many metabolic and cellular processes. As a result, lower glutathione levels have been linked to a number of chronic diseases. These include those associated with premature ageing, Alzheimer's and Parkinson's diseases, cancer, infertility, multiple sclerosis and chronic liver disease. How does glutathione help our body function on a daily basis?

• Supports the immune system – glutathione is an important component of a healthy immune system, especially in older people and athletes. It detoxifies the body, blocking the processes that lead to the development of cancer, ensures rapid regeneration of the body, and strengthens overall resistance to environmental and psychological stressors.

• Useful in the treatment of infertility – oxidative stress affects the reproductive health of both women and men. Glutathione is one of the body's natural weapons against oxidative stress, present in both male and female gametes. Studies indicate that high levels of glutathione in male and female gametes are associated with greater fertility.

• Anti-ageing effects of glutathione – from around the age of 50, glutathione levels begin to decline. Since low glutathione levels are associated with disease and premature death, it is in our interest to maintain stable levels. What's more, glutathione may be equally important in preventing neurodegenerative diseases such as Alzheimer's and Parkinson's.

• Effect on insulin resistance – increasing glutathione levels improves insulin resistance and promotes healthy fat burning. The substance therefore contributes to weight control in older people, both with and without diabetes.

Glutathione – what are its properties?

Glutathione is a tripeptide composed of three amino acids: glutamate, cysteine and glycine. It is involved in hydrogen transport, thus participating in tissue repair, protein production and immune system function. The substance has the following properties:

• Antioxidant health protection – glutathione is primarily an excellent antioxidant. It fights aggressive oxygen and hydrogen radicals, which damage cells and tissues. In addition to protecting our body against oxidative stress, glutathione also supports the regeneration of other important antioxidants, such as vitamin C and vitamin E;

• General detoxification of the body – glutathione binds to substances that need to be excreted, especially xenobiotics, i.e. chemicals such as pesticides and preservatives. It removes heavy metals and harmful mould toxins from the body, ensuring the health of the kidneys and liver;

• Immunostimulatory ally – from an immunological point of view, glutathione plays a special role in our survival. It protects immune cells from oxidative attacks and also increases the activity of immune cells themselves. Ultimately, high concentrations of reduced glutathione strengthen the entire immune system;

• Cell division regulator – glutathione also plays a role in cell division. The substance ensures healthy cell growth by regulating DNA formation and repair. It also protects protein structures from potential damage, ensuring longer youth and health.

Glutathione supplementation – potential side effects

Research on the side effects of L-glutathione is not very extensive, so there is little data available on this topic. However, there are some reports suggesting that consuming too much glutathione-containing products may manifest itself in, among other things:

• Rash

• Liver dysfunction

• Abdominal cramps

• Low zinc levels

• Thyroid imbalance

• Difficulty breathing

Furthermore, it is unclear how safe it is to take glutathione during pregnancy or breastfeeding.

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