Glutathione – the Master Antioxidant (And Why You Can’t Take It Orally)

Glutathione – the Master Antioxidant (And Why You Can’t Take It Orally)

The health of your body relies on a state of balance. In order to be healthy, our immune system cannot be too strong or too weak; you cannot work out too much or too little; you cannot overeat or undereat. One of the dangers your body faces is internal, and comes from what are called “free radicals.” While it may sound like a political group or maybe a rock band, free radicals have that moniker because they are electrons that have escaped from their pair bonds at the edge of a cell. These free atoms act in a radical fashion, careening about the body trying to stabilize themselves with another electron so they are back in a pair. As they wander untethered to a cell, they can cause destruction, especially in large numbers. Antioxidants are important to mediate the damage free radicals cause, and are defined as “compounds that protect against cellular damage caused by free radicals and other toxins” (Murray, 2012). While the name implies that antioxidants only mediate oxygen, free radicals can actually be made of oxygen, nitrogen, lipids or proteins; it’s just that oxygen-based free radicals are the most well-known and commonly studied.  Free radicals are produced all the time from normal cellular metabolism, but they can also be introduced in large quantities due to illness, disease, or from external sources such as pollution, radiation, and certain chemicals. No matter how they manifest, free radicals contribute to oxidative stress, cellular damage, and disease.

In order to deal with the stress caused by free radicals, the body naturally produces antioxidants such as glutathione, vitamins C and E, and various enzymes. However, sometimes the level of antioxidants produced naturally is not enough (either from illness, age, or genetics), or the amount of free radicals in the body is too high (especially if from an external source). When this happens, supplementation is needed to enhance our internal defense mechanisms in order to neutralize free radicals and prevent them from causing damage. The antioxidant glutathione is a tripeptide (made of three individual peptides: cysteine, glycine, and glutamic acid) that is the most abundant free radical scavenger in our body. It is naturally found in high concentrations in the liver, and plays a critical role in detoxification processes there by binding to toxins and facilitating their removal from the body.  Clinical studies have shown that “reduced glutathione concentration and/or a disproportionate ratio of GSH:GSSG [glutathione to oxidized glutathione] has been associated with a number of diseases, including cancer, human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), hepatitis, type 2 diabetes, Parkinson’s disease, and cystic fibrosis” (Allen & Bradley, 2011). This is because glutathione deficiency contributes to oxidative stress, which plays a key role in these and other disease pathogenesis such as seizures, Alzheimer’s disease, liver disease, sickle cell anemia, cancer, heart attack, stroke, and diabetes.

Of all the antioxidants studied, glutathione is considered the Master Antioxidant for five reasons. First, it has the ability to donate electrons to neutralize free radicals. So instead of the single electron running around looking for a partner and causing damage, glutathione steps in and gives it an electron which calms it down and neutralizes it. Second, glutathione has the power to react with certain enzymes to regenerate other antioxidants such as vitamins C and E. Third, it is an anti-cytotoxic so it helps prevent cell death. Fourth, it regulates cellular proliferation and apoptosis, helping to ensure that not too many or too few cells are produced. Fifth is essential to mitochondrial function, and we all know the mitochondria are the powerhouse of the cell. All of these functions contribute to the multifactorial power of glutathione’s antioxidant properties.

So now that we know how amazing glutathione is, how do we take it as a supplement to help maintain health and recover from illness? While it is possible to take glutathione orally, it is not very effective taken that way for two reasons. The first is because it is broken down in the digestive system and liver, so only a small amount of it is absorbed intact into the bloodstream. The second is because the body tightly regulates the production of glutathione, so taking it as an oral supplement has been clinically shown to not increase the levels of glutathione in the body to a therapeutic amount. The best way to  take glutathione in order to maintain cellular health and prevent oxidative stress-related diseases is via injection or inhalation. These methods can deliver higher levels of glutathione directly into the bloodstream or lungs, bypassing the digestive system and liver. By adding additional glutathione intravenously, the body’s white blood cells are given assistance in combating cellular dysregulation and pro-inflammatory cytokines. In addition to it being helpful, it is very well tolerated and the only risk to taking glutathione is if someone is allergic to it (which is exceedingly rare). Those with asthma should  glutathione intravenously and not as an inhalant, and of course those pregnant or breastfeeding should always check with their clinical provider first.


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About the author: Mary Genevieve Carty, MS, MHEd holds Masters degrees in Complementary and Integrative Health as well as Higher Education and is currently a doctoral student in Health Science at George Washington University’s College of Medicine and Health Science.  She is passionate about holistic health and wellness, and has additional training in teaching, Reiki, and Tapping/ Emotional Freedom Technique. Her research interests include resiliency, psychoneuroimmunology, neuroplastic pain, placebo/ nocebo effect, and bioenergy therapies.  The views she expresses are her own, and do not reflect any affiliation.

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Medically reviewed by Dr. Stephen Matta, DO, MBA CAQSM and Mary Anne Matta, MS, MA, LAC

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