Given that a vaccine for COVID-19 is quite possibly a long way off, it is more important than ever to explore other avenues of protecting your health. Even if a successful vaccine becomes available, it will be many years before entire populations can be immunized. Strong scientific evidence is now implicating oxidative stress in individual’s susceptibility to detrimental health outcomes with COVID-19 [1, 2].
Some recent studies have shown that profoundly serious infections with COVID-19, and its associated high risk of death, are due to glutathione deficiency . Additionally, a preliminary pilot trial with two COVID-19 patients found some improvement in respiratory symptoms after dosing with glutathione . This has led to several researches advocating the use of either glutathione itself [3, 5] or N-acetylcysteine  as a treatment for COVID-19 patients. Although the intention to increase cellular glutathione is likely to be of benefit for the reasons outlined below. The newly available precursor to glutathione called gamma-glutamylcysteine is more likely to be a more effective and rapid way of increasing cellular glutathione .
COVID-19, like the common influenza virus, belong to the family of RNA viruses. Much evidence has accumulated over the past decade suggesting that patients infected with such RNA viruses are under chronic oxidative stress  associated with glutathione depletion because oxidative stress, and the associated overproduction of reactive oxygen species, is a hallmark of RNA viruses. More importantly, an oxidative state promotes protein glutathionylation (S-S disulphide binding of glutathione to a cysteine residue). This provides a mechanism for RNA viruses to regulate and sequentially control the activity of the enzymes responsible for their replication cycle [3, 9]. This is particularly concerning if you already have low glutathione. An infection with COVID-19 could lower your glutathione below a critical point where oxidative stress progressively leads to tissue damage and organ failure.
Glutathione is the most important antioxidant defense in the lungs  and there is diverse scientific and medical literature that points to glutathione as a key player in not only preventing oxidative stress but also strengthening your immune system . The elderly, and those affected by chronic disease, especially the respiratory and immuno- compromised, seem to be most vulnerable to COVID-19 infection and its complications . This section of the population is well known to have lower than normal glutathione levels and often suffer extensively from oxidative stress [12-16].
There is also evidence to support that increasing your glutathione may also act as a prophylactic to viral infection. A study published in 2003  demonstrated that glutathione has anti-influenza properties. COVID-19, just like influenza, affects the oral, nasal, and upper airway and therefore oxidative stress, or other conditions that deplete glutathione, make you more vulnerable to such RNA virus infections.
Until recently, it has not been possible to increase patient’s glutathione rapidly when needed. This is due to the many obstacles of glutathione supplementation. The most obvious solution, oral or intravenous glutathione, does not work effectively and neither does N-acetylcysteine. The latter has shown some improvement in influenza type symptoms, however they did not seem to significantly affect the rate of infection . This is hardly surprising, since N-acetylcysteine is not an effective way of increasing cellular glutathione unless acutely depleted [19, 20]. Therefore it has been almost impossible to determine if increasing a patient’s glutathione is effective in antiviral therapy, and studies to that effect have consequently only been of limited success [18, 21-24]
There is some recent evidence coming out of China that supplementation with vitamin C is helpful in COVID-19 infection . It is interesting to note that glutathione is responsible for recycling cellular vitamin C and, in turn, vitamin C helps to lessen glutathione depletion . The recent availability of gamma-glutamylcysteine promises to be a game changer in the field of glutathione supplementation. It has been proven to be not only an effective way of supplementing glutathione, but also does so rapidly . It is hypothesized that increasing glutathione by administration of gamma-glutamylcysteine will not only prevent but also treat the debilitating effects of oxidative stress on patient’s health. It will also potentially disrupt the COVID-19 virus replication cycle halting the progress of the disease.
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- Liu, F., et al., Intravenous high-dose vitamin C for the treatment of severe COVID-19: study protocol for a multicentre randomised controlled trial. BMJ open, 2020. 10(7): p. e039519-e039519.
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