What is Glutathione?
As Glutathione is made up of amino acids, in the first instance it is necessary to understand a little about this class of chemicals. Amino acids are organic compounds that are composed of amine (a derivative of ammonia) and carboxylic acid combined with a ‘side-chain’. A side-chain is a group of chemicals that attaches to the main part of a molecule (sometimes referred to as the “main chain”). Oxygen, nitrogen, hydrogen and carbon are the primary elements found in amino acids. In the form of protein, amino acids are a primary component of human tissue, cells and muscles. In non-protein form, they are crucial in other biological functions such as neurotransmission. Because they are so biologically important to the composition of the human body, they are often used in the manufacture of products such as fertilisers, foods and medicines. Currently, there are approximately 500 different amino acids that are known1.
Glutathione is referred to as a tripeptide, that is, a compound of three separate amino acids. As it can be created (or synthesised) in the human body it is not described as an essential nutrient. Essential nutrients are those that have to be acquired directly via food intake. It is an antioxidant.
As the name suggests, an antioxidant hinders the chemical process known as oxidisation, which is the transmission of either electrons or hydrogen to a substance (known as the oxidising agent). A product of these reactions can be the production of free radicals- ions, molecules or atoms with unpaired electrons (electrons usually function in pairs). Because these free radicals are highly chemically reactive, they can trigger chemical chain reactions which can damage, or destroy entirely, cells, including human cells.
As such, human organs can be damaged by this oxidisation process. The brain is considered the most vulnerable of all organs to oxidative damage (Reiter R (1995). “Oxidative processes and antioxidative defense mechanisms in the aging brain” FASEB J 9 (7): 526–33. PMID 7737461). Therefore, medical experts recommend that people consume a diet that contains a large number of foods that are rich in antioxidants. Additionally, antioxidants are typically used as part of the medical treatment of brain injuries.
Specifically, glutathione has an extremely important role in the function of the human liver. It assists the liver in detoxifying harmful substances, and can attach itself to and destroy heavy metals including mercury, cadmium and lead (this process is known as chelation). As well as decreased liver function, low glutathione levels in the body can lead to muscle wasting and a less effective immune system (Dröge, Wulf; Holm, Eggert (1997). “Role of cysteine and glutathione in HIV infection and other diseases associated with muscle wasting and immunological dysfunction”.
The FASEB journal : official publication of the Federation of American Societies for Experimental Biology 11 (13): 1077–89. PMID 9367343). This effect can be observed in HIV/AIDS and cancer sufferers as well as numerous other diseases. It can even be seen in certain circumstances in athletes who have overtrained. Psychiatric illnesses such as schizophrenia and bipolar disorders are also associated with low levels of glutathione.
Glutathione is formed in the body via the synthesis of the following three chemicals: cysteine, glutamic acid and glycine. As such, one way that we can try to increase our glutathione levels is to look to consume foods that contain cysteine so that, in turn, the human body will synthesise more glutathione. Foods known to be high in cysteine include: chicken, egg yolks, oats, Brussels sprouts, broccoli, onions, red peppers and garlic.
Glutathione supplementation has also been considered as a method for increasing glutathione levels in the human body, particularly in patients who are ill with other diseases such as those listed earlier. However, this has proven fairly ineffective. Research has established that even administering an extremely large dose of glutathione orally does not result in a consequent increase in the patient’s glutathione level (Witschi, A.; Reddy, S.; Stofer, B.; Lauterburg, B. H. (1992)”The systemic availability of oral glutathione”. European Journal of Clinical Pharmacology 43 (6): 667–9. PMID 1362956). It is thought that this is because the stomach does not absorb glutathione very well if it is administered orally. Intravenous administration has also been tried although, again, evidence suggests that this is of limited effectiveness. In spite of this, glutathione injections are now even being offered in the beauty sector, with the accompanying marketing often suggesting the benefits to be whiter skin, as well as miscellaneous health gains from an increased level of antioxidants in the body (disease and aging prevention, for example).
Those who have taken glutathione supplements over a period of time have occasionally displayed zinc deficiencies, as well as reports of cramps in the intestinal area and a feeling of bloating. In the latter cases, an increased water intake is suggested as the remedy. Those who are allergic to the protein found in milk, casein, should not take glutathione.
Additionally, people who have undergone organ transplants should not take glutathione because it may interfere with the immunosuppressive drug regime, which is necessary to ensure the donated organ is not rejected by the body.
Glutathione has also been shown particularly effective in improving male fertility.
In conclusion, we have established that glutathione is a non-essential nutrient that is composed of amino acids, and is synthesised within the human body. It is a powerful anti-oxidant, and glutathione deficiency is associated with lowered liver function and muscle wasting. Glutathione deficiency is often present in patients suffering from serious illnesses such as HIV/AIDS and cancer. It is not a straightforward process to raise deliberately a human’s glutathione level; one of the only effective ways of doing so is to consume food that is rich in cysteine, one of the chemical components of the compound. Supplementation, both oral and intravenous, has been found to be of only limited effectiveness.
- “Wagner, Ingrid; Musso, Hans (November 1983). “New Naturally Occurring Amino Acids”. Angew. Chem. Int. Ed. Engl. 22 (22): 816–828)” ↩