There are more questions than answers surrounding Covid-19, my friends, and one of those many questions relates to vitamin D. More specifically, there’s a question of whether there is a link between vitamin D deficiency and a person’s chances of catching this illness.
Well, I have to tell you that I’ve combed over a lot of data and my answer is: it’s complicated.
As reported by The University of Chicago Medicine, some studies have demonstrated a possible link between low vitamin D levels and the odds of someone getting Covid-19 (https://www.uchicagomedicine.org/forefront/coronavirus-disease-covid-19/vitamin-d-deficiency-may-raise-risk-of-getting-covid19).
In a study conducted at the university, researchers looked at 499 Covid-19 patients who had their vitamin D levels measured within one year of being tested for Covid-19. Patients who were vitamin D deficient—defined as having blood levels of 20ng/ml or less—and who did not receive treatment for this deficiency, according to their medical records, were close to twice as likely to test positive for Covid-19 as patients who had sufficient vitamin D levels.
As noted by the study’s lead author, Dr. David Meltzer, vitamin D is necessary for healthy immune system functioning, and previous studies have linked vitamin D supplements to a decreased risk of catching viral respiratory tract infections.
However, it’s still unclear if there is a direct link between vitamin D deficiency and Covid-19 risk. The study authors themselves noted that more research is needed into what role, if any, vitamin D deficiency could be playing in the fight against Covid-19. This is partly because many people in the U.S. are vitamin D deficient to begin with, so seeing many Covid-19 patients with low vitamin D levels is not entirely unexpected. In addition, many studies were not able to control for the other conditions that could contribute to Covid-19 risk that the vitamin-D-deficient patients may have had.
Generally speaking, taking a vitamin D supplement at the recommended levels for your age isn’t a bad idea. Even if it turns out this vitamin does not do much to fight Covid-19, we do know it’s necessary for strong bones and muscle and nerve health. According to the National Institutes of Health, adults aged 19 to 70 years should take 15 mcg daily, while those over 70 should take 20 mcg daily (https://ods.od.nih.gov/factsheets/VitaminD-Consumer/). As with any other supplement, check with your doctor before you begin to take vitamin D on a regular basis.