Please ensure Javascript is enabled for purposes of website accessibility BREAKING NEWS ON IMMUNE SUPPLEMENTS! Vitamin C, Vitamin D, Zinc, & NAC

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science nutrition <strong>blog</strong>

By Steve Blechman


There currently are no products or dietary supplements that are scientifically proven to treat or prevent the coronavirus, according to the U.S. Food and Drug Administration (FDA). Still, some unethical supplement companies have promoted fraudulent cures and claims and treatments not based on good science, such as colloidal silver products for coronavirus. The FDA has cautioned that colloidal silver is not a safe or effective treatment for any disease or condition! By law, companies are not allowed to make claims on their product labels or ads that the product is intended to diagnose, treat, cure or prevent any disease. 

Research in the scientific literature has shown that certain immune dietary supplements and nutrients such as zinc, vitamin D, vitamin C, selenium, N-acetylcysteine, and polyphenols have potential immune modulating benefits. I reported on these nutrients in my recent article entitled, TOP 5 IMMUNE HEALTH SUPPLEMENTS. BATTLING THE DEADLY CYTOKINE STORM: What Science Says (May 18, 2020, I was so pleased by a recently reported Cleveland Clinic study! Researchers published a scientific review article (June 2, 2020, Cleveland Clinic Journal of Medicine) entitled: What is the role of supplementation with ascorbic acid, zinc, vitamin D, or N-acetylcysteine for prevention or treatment of COVID-19? This is a very important and significant article and requires further investigation and research. The Cleveland Clinic has pioneered many medical breakthroughs and has been known for many years as one of the best hospitals and medical institutions in the United States.

The authors outline, “the biological plausibility, applicable clinical data and potential role of each of these agents.” The Cleveland Clinic Investigators continued to say that, “several agents intended to supplement dietary intake or indigenous molecules may have a theoretical role in preventing or treating COVID-19.” Based on their scientific review, the authors further acknowledge that “ascorbic acid, zinc, vitamin D, and N-acetylcysteine have biologic plausibility for prevention and treatment of COVID-19 and are candidates for clinical trials evaluating patients with these indications.”

The authors mention that COVID 19 infection can cause an increase of systemic inflammation in the body. This inflammation is often referred to as the cytokine storm. The cytokine storm elevates levels of proinflammatory cytokines such as interleukin-6 (IL-6), interleukin-1 (IL-1), and tumor necrosis factor (TNF). The authors cite research that zinc, vitamin D and N-acetylcysteine (NAC) can lower these inflammatory cytokines. Research has shown that the cytokine storm causes a hyperimmune response that cannot only damage the lungs but also the heart, cardiovascular system, blood vessels, liver, pancreas, intestines, kidney and brain. The cytokine storm also causes severe blood clots all over the body, increasing the risk of heart attack, stroke, and pulmonary embolism.

Also mentioned in the article is that, “patients with COVID-19 likely have evidence of oxidative stress which is characterized by production of reactive oxygen species and reactive nitrogen species, and a concomitant efficiency of antioxidants.” These reactive oxygen species (ROS) can damage tissues and cause inflammation. Antioxidant supplements may be helpful. “Vitamin C, zinc, vitamin D and N-acetylcysteine have been hypothesized to be useful for prevention or treatment of COVID-19.” N-acetylcysteine is a precursor of glutathione a very important antioxidant in the body, including the lungs. Also discussed in the review is the potential antiviral properties of vitamin C, decrease in coronavirus replication with zinc, antiviral, anti-inflammatory effects of vitamin D and N-acetylcysteine.

Another important antioxidant, not mentioned in the report, is the mineral selenium. Selenium functions as a co-factor for the synthesis of the antioxidant glutathione in the body. It was most recently reported by ScienceDaily on April 29 and published in the April 28 issue of the American Journal of Clinical Nutrition that an “international team of researchers led by professor Margaret Raymon at the University of Surrey, has identified a link between COVID-19 cure rate and regional selenium status in China.” This was a very exciting finding! Research has shown that selenium has anti-inflammatory and antiviral properties. More studies are needed to determine if selenium deficiency can increase the risk of COVID-19.

In conclusion, there is currently no dietary supplement that has proven to treat or cure COVID-19! The research on immune supplements and modulators discussed and reviewed in this article is very encouraging and promising but more well-designed, randomized controlled trials are needed to establish safety and efficacy.


©Published by from Advanced Research Media, Inc. 2020

©Reprinted with permission from Advanced Research Media, Inc.




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