By Steve Blechman

Winter is on its way! We know that 50% of Americans suffer from vitamin D deficiency, the “sunshine vitamin.” It makes sense to supplement the diet and help support immune function, especially during the cold winter, with limited sun exposure and flu season. It makes sense to supplement with vitamin D! And of course, the most recent surge in coronavirus cases in the U.S., Europe and other parts around the world.  The virus came roaring back and now Europe is considered the epicenter of rising infection cases globally. Covid cases are increasing at an alarming rate as colder weather arrives, and people go indoors.

The good news is that in the U.S. we are better prepared to deal with the virus surge and the infection fatality rate is going down, and hopefully a vaccine is near and available in 2021.

In a recent study published September 3, 2020 in the Journal of the American Medical Association (JAMA Network), researchers reported that 489 patients “in this single-center, retrospective cohort study likely deficient vitamin D status was associated with increased COVID-19 risk, a finding that suggests that randomized trials may be needed to determine whether vitamin D affects COVID-19 risk.”

The importance of this study is that, “Vitamin D treatment has been found to decrease the incidents of viral respiratory tract infections, especially in patients with vitamin D deficiency.” Vitamin D is important for regulating the immune system and help to reduce certain inflammatory cytokines.

Research has shown over the years that vitamin C, quercetin, and other polyphenols, found in grapes, are important antioxidants in the body that lower inflammation. Selenium, N-acetylcysteine (NAC) and zinc are important antioxidants in the body that can lower inflammation. When a virus particle enters your body through your nose, mouth or eyes, into your lungs, the immune system recognizes the virus and sends immune-signaling molecules called cytokines such as interleukin-6 (IL-6) and tumor necrosis factor (TNF). Normally these cytokines play a beneficial role by activating our innate immune response and certain white blood cells called macrophages, neutrophils and natural killer cells that destroy and kill certain dangerous pathogens, bacteria and viruses. These white blood cells are like killer, phagocytic Pac-Men that release reactive oxygen species (ROS) free radicals and kill these bacteria and viruses at the same time these ROS free radical species damage normal tissues and can cause inflammation and cell death. So these white blood cells in fact are a two-edged sword – they kill dangerous viruses and bacteria, or they can go haywire, causing severe inflammation, cell damage and organ failure. Antioxidant nutrients such as vitamin C, polyphenols, selenium, zinc and N-acetylcysteine (NAC) have been shown in the scientific literature to be potent scavengers of ROS and free radicals, helping to lower inflammation in the lungs and other organs and tissues.

Polyphenols such as quercetin and grape skins and grape seed extract are effective and work synergistically with vitamin C as antioxidants, having anti-inflammatory and antiviral properties. Quercetin appears to prevent viruses from entry in the cell, thereby reducing viral load (Viruses, December 2016). Polyphenols also function as prebiotics and help promote healthy bacterial flora. Curcumin, a polyphenol found in the spice turmeric, has anti-inflammatory properties. There are no studies that demonstrate curcumin prevents or reduces viral infections in humans. One concern is that curcumin may increase the expression of the ACE2 receptor that makes it easier for the virus to enter the cell. This is controversial, and more research is needed to clarify this.

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 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.

Especially during the winter months, we need to learn to live with the virus, but we can’t let it control our lives. As always, I am eating very healthy, following the Mediterranean diet, and taking my immune support supplements: N-acetylcysteine, vitamin C, polyphenols (such as quercetin, grape skin and grape seed extract), zinc, selenium, and vitamin D. As always, I am exercising daily, and coping better when dealing with daily stress with meditation and relaxation techniques. I also practice social distancing, use a face mask, and properly wash my hands. Why take a chance at my age of 67? Better safe than sorry!

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). 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.

©Published by from Advanced Research Media, Inc. 2020

©Reprinted with permission from Advanced Research Media, Inc.

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