Are vitamin D supplements able to protect against COVID-19 and other infections?

Lack of vitamin D is rather common and taking large quantities of the nutrient can not only protect against virus infections like COVID-19 but even counteract the life-threatening complications in those affected with the disease, according to a new, comprehensive, Irish report (TILDA) from Trinity College Dublin (University of Dublin in Ireland). The TILDA report supports many other published studies showing that the immune system is unable to function without vitamin D. The main focus in the battle against COVID-19 is hygiene, isolation, and delayed immunization with vaccines. However, it is also essential to bolster the immune defense, as this determines the difference between being able to ward off the infection, suffer mild symptoms only, or succumb. The scientists recommend that all adults take a high-dosed vitamin D supplement, especially older people, nursing home residents, chronically ill people, hospital patients, health professionals and other exposed groups. That way, we are better protected against future epidemics.

Sun exposure during the summer period is the primary way to get vitamin D, and it is no coincidence that virus infections like COVID-19 typically occur during the winter period and taper off when the weather gets warmer. Still, there are many people who suffer from chronic vitamin D deficiency for various reasons, which we will take a closer look at. Eamon Laird and Rose Anne Kelly, two researchers affiliated with Trinity College Dublin, recently published a comprehensive report called TILDA, in which they describe vitamin D’s essential role in the immune defense and explain how widespread vitamin D deficiency among older people and other vulnerable groups contribute to problems like COVID-19. The accompanying complications cause a lot of suffering, they place an enormous burden on intensive care units, the death toll rises, and there are huge socioeconomic costs that follow in the wake of disease and lockdown.

Vitamin D activates the entire immune system

Vitamin D is primarily recognized for its role in bones and muscles but most cells in the body have vitamin D receptors that activate and control various genes and a host of different biochemical processes in the body. Vitamin D is essential for activation of the white blood cells that the immune system uses to attack microscopic enemies such as COVID-19. In our respiratory tract, we have a particularly large concentration of white blood cells that depend on vitamin D for being able to combat germs. Vitamin D also boosts certain antibiotic peptides in our lungs. If we lack vitamin D, the immune system remains passive. In other words, even if we have plenty of white blood cells they never go into action because they don’t receive the signals from their vitamin D receptors (VDR).

Vitamin D counteracts life-threatening inflammation and cytokine storm

Vitamin D inhibits the production of proinflammatory cytokines (e.g. interferon gamma and interleukin-6) that prevent the immune system from overreacting and causing tissue damage. According to the TILDA report that is based on a larger population study of people from 50 years of age and older, the ageing process changes the way our immune system reacts. What is often seen is low-grade inflammation, a characteristic trait of many chronic diseases like diabetes, asthma, and cancer. This chronic, low-grade inflammation makes patients more vulnerable.
When COVID-19 becomes complicated and life-threatening it is not due to the virus itself. It is because the immune defense sets in with a cytokine storm and hyperinflammation that cause acute respiratory distress syndrome (ARDS) and secondary damage to the cardiovascular system and other tissues. In other words, it is not COVID-19 that is the culprit, it is the overreactive immune defense that causes the weakest patients to succumb.
It is relevant to make a note of the fact that having adequate amounts of vitamin D in your blood helps protect against virus infections at the same time as counteracting the potentially harmful inflammatory processes that are seen with ageing and various chronic diseases and when influenza and COVID-19 become life-threatening.
According to a large meta-analysis of 25 studies with 10,933 participants from 15 different countries, vitamin D supplements help prevent colds (that are often caused by a different type of coronavirus), influenza, and acute respiratory tract infections such as bronchitis and pneumonia.
Vitamin D has a significant protective effect when taken on a daily basis or once a week in very large doss. The scientists behind the above-mentioned meta-analysis say that it is safe to take vitamin D and the nutrient is especially effective for protecting against virus and respiratory tract infections in people who are vitamin D-deficient to begin with.
A meta-analysis from 2019 with 21,000 participants from eight studies showed that participants with low blood levels of vitamin D were 64 percent more likely to contract pneumonia, which is a complication that is seen in connection with influenza. The scientists therefore say that having sufficient amounts of vitamin D in your blood may be an advantage for preventing COVID-19 and any complications in the respiratory tract or other places, in cases you catch the virus.

The TILDA report reveals widespread vitamin D deficiency

The TILDA report uses data from a population study called The Irish Longitudinal Study on Ageing. Since 2009, this study has followed 8,172 home-living people from the age of 50 years and older. The scientists have collected various types of information about the participants and their physical and mental health, genetic conditions, living conditions, diet habits, weight, smoking habits, exercise habits, and lung function. The participants’ use of vitamin D and other nutritional supplements was also registered. Blood levels of vitamin D were measured and divided into three categories: deficiency (less than 30 nmol/L), insufficiency (30-50 nmol/L) and sufficient (over 50 nmol/L). The results showed that:

• Eight percent of all participants older than 55 lacked vitamin D during the summer period
• Thirteen percent of all participants older than 55 years were vitamin D-deficient all year round
• Twenty-seven percent of participants older than 70, who primarily stayed indoors, had deficiencies
• Forty-seven percent of participants older than 85 years were deficient during the winter period

In Denmark, studies have revealed that around 50 percent of the population has minor vitamin D deficiency while around 15 percent of people are moderately vitamin D-deficient

Risk factors of deficiency and poor utilization of vitamin D

As mentioned earlier, the sun during the summer period is our main source of vitamin D. We synthesize the nutrient in our skin through conversion of a cholesterol precursor. We start by producing a vitamin D precursor that is activated in the body by the liver and kidneys. This activation requires the presence of magnesium-containing enzymes, which means that being magnesium-deficient can impair the body’s utilization of vitamin D. Ageing processes, being dark- skinned, using too much sun factor creme, being overweight, having diabetes, and using certain types of medicine such as cholesterol-lowering statins can also lower the body’s vitamin D status. Similarly, smoking and being physically inactive increases the risk of being vitamin D-deficient.
According to the TILDA report, those participants that suffered from chronic lung diseases (like bronchitis, asthma, and emphysema) had significantly lower vitamin D levels both during the summer and winter period. This widespread lack of vitamin D therefore contributes to making COVID-19 far more dangerous for senior citizens, dark-skinned individuals, overweight people, smokers, nursing home residents, and the chronically ill.

Scientists call for new health policy concerning vitamin D

According to the researchers behind the TILDA report, there is no official health policy for vitamin D in Ireland, and they refer to the United States and Canada where many foods are enriched with vitamin D. They also mention Finland where the vitamin D-enrichment of foods and a more systematic health policy concerning supplements helped lower vitamin D deficiency to a point where it affects less than one percent of the Finnish population.
In a new article that is published in Irish Medical Journal, the scientists recommend that adults take 20-50 micrograms of vitamin D every day to reap the same benefits. This is a very important recommendation while we await an effective vaccination. Taking high-dosed vitamin D supplements is also important to help protect us against new coronavirus strains. Dr. Declan Byrne from St. James Hospital and School of Medicine at the Trinity College in Dublin also mentions how important vitamin D supplementation is, especially for older Irish people, hospital patients, nursing home residents, and health professionals. The same goes for the normal, healthy population.
Blood levels of vitamin D should be at least 50 nmol/L, and levels of 75-120 nmol/L may be even better. In order to reach these levels, you need to take a daily vitamin D supplement from October to May. If you do not get enough sun during the summer period, you must take vitamin D all year round. The actual need for vitamin D depends on things like age, skin type, BMI, smoking habits, chronic illnesses like asthma and diabetes, and the use of cholesterol-lowering statins. According to the European Food Safety Authority (EFSA), the upper safe intake level for vitamin D is 100 micrograms daily.
Vitamin D is a lipid-soluble vitamin, which means that the best absorption and utilization of the nutrient is obtained with supplements where vitamin D is dispersed in oil. Also make sure to eat plenty of green, coarse foods that contain a lot of magnesium because different magnesium-dependent enzymes are needed to activate the form of the vitamin D that we get from sun exposure and from supplements.

References:

Eamon Laird, Rose Anne Kenny. Vitamin D deficiency in Ireland – implications for COVID 19. Results from the Irish Longitudinal Study on Ageing (TILDA) April 2020

Will Chu. Could vitamin D play a role in coronavirus resistance? Research thinks so. NUTRA ingredients.com April 2020

William B. Grant et al. Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and Covid-19 Infections and Deaths. Nutrients 2020

William B. Grant. Vitamin D Supplementation Could Prevent and Treat Influenza, Coronavirus, and Pneumonia Infections. Nutrients 2020

D.M McCartney, D. G. Byrne. Optimisation of Vitamin D Status for Enhanced Immuno-protection Against Covid-19. Irish Medical Journal. 2020

Essen MR et al. Vitamin D controls T cell antigen receptor signaling and activation of human T cells. Nat Immunol 2010

University of Copenhagen. Vitamin D crucial to activating immune Defences. 2010

Qi Dai el al. Abstract CT093: Bimodal relationship between magnesium supplementation and vitamin D status and metabolism: Results from randomized trial. Cancer Research July 2018

https://www.sundhed.dk/sundhedsfaglig/laegehaandbogen/endokrinologi/tilstande-og-sygdomme/knoglevaev-og-vitamin-d/d-vitamin-mangel/