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Can Vitamin D Help Guard Against Coronavirus?

John is a Mid-Atlantic writer covering health issues, personal well being and a range of other topics

Coronavirus (COVID-19)

Coronavirus (COVID-19)

We are now in the middle of the worldwide pandemic of a coronavirus, more specifically: COVID-19. We must do all we can avoid catching it, spreading it, and putting an unnecessary burden on health care workers and first responders.

Vitamin D is known to reinforce our immune systems. Can Vitamin D help our immune system fight against Coronavirus? Based on my research, here's what I discovered.1

Since writing this article, more and more evidence has been found linking Vitamin D deficiency and COVID-19. For example, three doctors authored a January 2021 op-ed piece in MedPage Today: Don't Let COVID-19 Patients Die With Vitamin D Defiency. They reported one study that found that 97 percent of patients hospitalized with ICU admissions were vitamin D deficient while 33 percent of asymptomatic patients were deficient in vitamin D. Other studies showed similar results.

Can Vitamin D Help Fight Coronavirus?

According to Dr. Holick, professor of medicine at Boston University Medical Center, "Given the newness of the coronavirus (COVID-19), no research has studied how vitamin D levels might be associated with the incidence or severity of a coronavirus infection. However, at this time I believe it is prudent to make sure everyone has adequate vitamin D levels.”

According to Dr. Frieden, former CDC Chief, "Higher COVID-19 mortality rates among older people and those with chronic conditions suggest that a weakened immune system contributes to poor outcomes . . . science supports the possibility -- although not the proof -- that vitamin D may strengthen the immune system, particularly of people whose vitamin D levels are low."

Although currently, there is no evidence that vitamin D has any effect on COVID-19 infections, it makes sense to have sufficient levels of vitamin D so that our immune system can function at top capacity.

What Is Coronavirus?

"Corona" is Latin for "crown." A virus is a microscopic agent that infects and replicates inside living organisms. There are literally millions of different types of viruses that can infect animals, plants, and microorganisms. "Coronavirus" is a large family of viruses that can infect animals. A single coronavirus virion is spherical in shape with numerous tiny club-shaped spikes that give the effect of a corona surrounding the virion.

The 2019 novel Coronavirus (COVOD-19) is a new virus that can spread person to person and can cause serious and sometimes fatal respiratory illness in people. Sneezing, coughing, and touching are principal ways it spreads. It can linger on surfaces for hours.

What Is Vitamin D?

A vitamin is an organic compound vital for the human body that cannot be made by the body. Vitamin D is different. It is actually a hormone, with far-reaching vital effects on all parts of the body. Unlike other "vitamins" it can be made by the body. It is produced in the skin all over the body from the ultraviolet B portion of the sun's rays. From the skin, vitamin D moves to the liver where is transformed into a form that can be further transformed by the kidney and other parts of the body, including immune cells, into the active form that has benefits in every part of the body.

In addition to the sun's ultraviolet B, there are two other sources of vitamin D: diet and supplements. Certain foods like wild salmon, fortified milk, and mushrooms are rich in vitamin D. Dietary supplements containing vitamin D can be purchased over the counter.

How Does Vitamin D Strengthen the Immune System?

Vitamin D receptors are everywhere in the body. Vitamin D acts as the sentinel strengthening the immune system guarding human health. The immune system produces antibodies or white blood cells that attack invaders such as viruses. A healthy immune system depends upon sufficient vitamin D levels in the body.

According to Dr. Michael F. Holick, "Contrary to popular wisdom, vitamin D isn't just about bone health . . . vitamin D is actually a hormone that plays a central role in metabolism and also in muscle, cardiac, and neurological functions as well as inflammation . . ."

If I had to give you a single secret ingredient that could apply to the prevention--and treatment in many cases--of heart disease, common cancers, stroke, infectious diseases from influenza to tuberculosis, type 1 and 2 diabetes, depression, insomnia, muscle weakness, joint pain, fibromyalgia, osteoporosis, psoriasis, multiple sclerosis, and hypertension, it would be this: vitamin D.

— Dr. Michael F. Holick, Ph.D,, M.D.

How Much Vitamin D Do I Need?

In 2011, the Institute of Medicine put out a major report on dietary intake levels for calcium and vitamin D to maintain health and avoid risks of taking too much. Note that these are just general recommendations for daily intake, not for specific diseases or conditions.

After reviewing nearly 1000 research studies and hearing testimony, the report came to the following conclusion:

"600 IUs [of vitamin D] daily meets the needs of almost everyone in the United States and Canada, although people 71 and older may require as much as 800 IUs per day because of potential physical and behavioral changes related to aging."

"The majority of Americans and Canadians are getting enough vitamin D and calcium, the committee determined from reviewing national surveys of blood levels."

Committee Chair Catharine Ross emphasized that "Amounts higher than those specified in this report are not necessary to maintain bone health." [emphasis by John Dove.]

That report also says that the upper intake level for vitamin D that represents the upper safe boundary for all persons over 8 years old is 4000 IUs per day. They stress that this should not be misunderstood as amounts people need or should strive to consume.

Dr. Michael F. Holick, who has spent over 30 years studying vitamin D and the human body, responded to the IOM report:

"I recommend to all of my patients that they should take 2000-3000 IU of vitamin D a day from dietary sources, sensible sun exposure and supplements. I believe that it is important for women to take at least 2000 IU of vitamin D a day. Although many of the studies are association studies there continues to be strong evidence that increasing vitamin D intake has other health benefits besides those for bone health. From my perspective there is no downside to increasing your vitamin D intake to levels I have recommended in The Vitamin D Solution which is 1000 IU of vitamin D a day for children and 2000-3000 IU of vitamin D for adults."

My Vitamin D 2000 IU Daily Supplement

How Do I Personally Get Enough Vitamin D?

So what do I make of the varying vitamin D recommendations? I decided to follow Dr. Holick's recommendation of daily vitamin D intake from sun, diet, and supplements of 2000-3000 IUs of vitamin D for adults. I started this regimen some years ago, and I see no reason to stop now.

I get my vitamin D in three ways:

  1. Sun exposure. Every day that I can, I go outside and sit facing the mid-afternoon sunshine for about 10-15 minutes. I know that the sun's ultraviolet B rays are only available from about 11 to 3 o'clock each day in spring, summer, and fall. However, every day that I can, I go outside and sit feeling the warmth of the sun on my face. I do this not only for vitamin D but also to reinforce my circadian rhythm.
  2. Diet. I like salmon and eat it as often as I can, My morning cereal is made with vitamin D fortified milk. I choose fruits and vegetables that are high in vitamin D.
  3. Supplement. I take a daily multivitamin supplement that contains 500 IUs of vitamin D, plus another vitamin supplement of 2000 IU for a total vitamin D supplement intake of 2500 IUs.

There is no conclusive evidence that I am protected against coronavirus. Nevertheless, I feel I have done the best I can to protect and support my immune system against diseases—including coronavirus.

Selected References for Further Reading

Among the numerous references on subjects relating to this Hub, I've chosen the following for your further reading:

R. H. Carmona, M.D., M.P.H.; V. G. Thakker, M.D.; J. C. Umhau, M.D., M.P.H. "Don't Let COVID-19 Patients Die With Vitamin D Defiency," MedPage Today, 5 Jan 2021.

2010/2011 Institute of Medicine Report Sets New Dietary Intake Levels for Calcium and Vitamin D, Press Release, National

Dietary Reference Intakes for Calcium and vitamin D to Maintain Health and Avoid-Risks Associated with Excess, National Academies Full Report

Former CDC Chief Tom Frieden: Coronavirus Risk May be Reduced with Vitamin D, Opinion: Fox News

Michael F. Holick, Ph.D., M.D., The Vitamin D Solution: A 3-Step Strategy to Cure Our Most Common Health Problem, (New York:Hudson Street Press, Penguin Group), 2010

Michael F. Holick website, "coronavirus," "virus," "pandemic, "immune system"

More News Articles on Vitamin D and Coronavirus

Since I wrote this article on 26 March 2020 the Coronavirus (COVID-19) has grown worse -- Over 1.2 million reported cases and over 74,000 deaths (as of 8 May 2020). People are desperately looking for ways to fight this terrible disease. Researchers, doctors, and others are reporting new studies that show that persons deficient in Vitamin D may be less likely to fight off COVID-19.

Here is a good article by Marilyn Wedge Ph.D., Vitamin D and COVID-19: Can taking Vitamin D save your life? Dr. Wedge summarizes recent studies that reported detrimental effects of low Vitamin D levels and the ability to fight Coronavirus. She says . . .

. . . having a robust Vitamin D level may play a significant role in preventing COVID-19. Recently, a string of studies has identified Vitamin D deficiency as a risk factor for the disease.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.