What Is Glutathione? A Potent Antioxidant

Page content

During the normal functioning of cells and cellular processes, molecules are generated that are not stable. These molecules tend to have one extra electron or they are missing an electron. To become stable, these molecules react with stable molecules to either gain an electron or donate an electron. In the process, the stable molecules become reactive, leading to cellular and tissue damage. These unstable molecules are called free radicals. The actions of free radicals are countered by a group of molecules called antioxidants. Antioxidants interact with free radicals before they react with stable molecules. Unlike other molecules, antioxidants have the unique ability to stabilize free radicals without becoming unstable themselves. The most potent antioxidant in the body is glutathione. It is often considered the ‘master’ antioxidant.

What is Glutathione?

Glutathione is a protein produced by all cells in the body from the amino acids cysteine, glutamic acid, and glycine. The biosynthesis of this protein occurs in two steps, each catalyzed by an enzyme. The first step is the reaction between cysteine and glutamic acid to generate gamma-glutamylcysteine. The reaction is catalyzed by glutamate-cysteine ligase. The second step is the addition of glycine to gamma-glutamylcysteine with the aid of the glutathione synthetase enzyme.

The majority of glutathione’s activity is due to the thiol group (-SH) of cysteine. This part of glutathione features a sulfur-hydrogen molecule bonded to the carbon chain. It is capable of donating the hydrogen atom, which is essentially donating an electron, in its reduced state. After donating the electron, glutathione is oxidized and it quickly reacts with another oxidized glutathione molecule to form glutathione disulfide.

How Does the Body Use Glutathione

Glutathione has several functions at the cellular level. The main role of glutathione is to act as an antioxidant. It protects cells from the damaging effects of free radicals and reactive oxygen compounds. In fact, glutathione is the primary antioxidant produced by cells. Red blood cells produce a lot of glutathione to mitigate the oxidative stress caused by peroxides. Glutathione also bolsters the antioxidant effects of several molecules that are obtained through the diet including vitamin C and vitamin E. Together, these molecules ensure that several biological processes are functioning normally by acting as antioxidants.

Glutathione also protects cells from several foreign substances through direct interaction with the molecules. Some of these compounds may be able to cause cancer or are toxic to cells. Glutathione reduces the effects that these foreign molecules have on the normal functions of a cell.

Glutathione is required for synthesis and maintenance of other biomolecules. This includes the synthesis of DNA, which is the genetic material present in the nucleus of all cells, and the synthesis of prostaglandins, which are lipid molecules synthesized from fatty acids. Glutathione is involved in the repair of DNA and in the transportation of amino acids. This antioxidant may also play a role in regulating several molecules in the immune system including cytokines and lymphocytes.

Food Sources, Supplements, and Deficiency

Glutathione is not naturally found in food. It is synthesized by the body using molecules which are present in food, including cysteine, glutamic acid, and glycine. So, it’s not an essential nutrient and deficiency is extremely rare. There are foods, which you can consume to try and boost glutathione levels. The goal is to eat more foods that contain the precursors of glutathione, namely the amino acids mentioned above. Also, it is recommended to consume foods that contain glutathione peroxidase. Some of the foods, which meet these criteria include avocados, asparagus, broccoli, garlic, raw eggs, spinach, and tomatoes.

Supplements that contain glutathione generally do not boost the level of this antioxidant in the blood. The activity of supplemental glutathione is generally lost in the digestive process. Supplements that contain precursors of glutathione are somewhat effective at increasing glutathione levels. These include n-acetyl-cysteine, s-adenosyl-l-methionine, and whey protein supplements.

There is a rare genetic disorder that causes extremely low levels of glutathione called glutathione synthetase deficiency. The enzyme responsible for producing glutathione is unable to function normally. Mutations of certain genes are responsible for this, and the lack of adequate glutathione causes neurological problems and acidic blood pH.

Conditions Which May Benefit From Glutathione

Free radical damage can lead to several conditions including premature aging, heart disease, and cancer. By mitigating the damage caused by free radicals, the chances of developing these conditions is reduced. Glutathione may also prevent diabetes, reduce anxiety, and lessen herpes outbreaks. More studies are needed to prove that glutathione benefits these conditions.


1. Glutathione supplement pill health benefit and side effects - https://www.raysahelian.com/glutathione.html

2. What Foods Have Glutathione? - https://www.amazing-glutathione.com/

3. S-adenosyl-L-methionine: its role in the treatment of liver disorders - https://www.ncbi.nlm.nih.gov/pubmed/12418503

4. Improved glutathione status in young adult patients with cystic fibrosis supplemented with whey protein - https://www.ncbi.nlm.nih.gov/pubmed/15463873

5. Glutathione Synthetase Deficiency - https://emedicine.medscape.com/article/944368-overview#showall