Does Vitamin D fight COVID19?
Unfortunately vitamin D is probably not going to save you from Coronavirus, although we all wish it was something as simple as that. Vitamin D, which in general is thought of as the vitamin related to bone health, certainly does have effects on the immune system and the body’s response to infection. Vitamin D helps keep mucosal defenses strong and prevent excessive inflammation. Past research has shown that vitamin D supplementation lowers the likelihood of getting respiratory tract infections, so naturally, scientists have started to investigate if there’s a connection between vitamin D and coronavirus infection and disease severity. While this area is certainly worth researching, most of the existing studies have looked just at associations and correlations, which cannot prove cause and effect. A few studies out of Europe have indicated that low vitamin D levels are associated with more severe disease. The studies used the latitudes of the countries as proxies for vitamin d levels. For example, Spain and Italy have higher rates of vitamin D deficiency and have experienced the highest infection and death rates in Europe, so one study posited that “optimising vitamin D status…will have potential benefits for Covid-19.” A study out of the UK that used previously collected vitamin D data compared to Covid test results, however, said “Our findings do not support a potential link between vitamin D concentrations and risk of COVID-19 infection.” Finally, a study looking at high dose vitamin D supplementation as a potential treatment for critically-ill patients with low vitamin D showed no benefit.
So for now, rather than ordering a bunch of vitamin D, it’s safest to assume that a number of factors (with complex interactions,) including age, general health, race, access to healthcare and genetic factors, determine the clinical course after exposure to SARS-CoV-2. All that said, taking a daily multivitamin is generally safe for most people (the Recommended Dietary Allowance (RDA) of Vitamin D is 600 IU daily and 800 IU if you are older that 70 years of age), but please keep social distancing, wearing masks and washing your hands as those continue to be proven methods to decrease your risk of getting coronavirus in the first place.
(Jackie Phillips, MD, May 18, 2020)