While earlier studies had suggested low blood levels of vitamin D might increase the severity of COVID-19 infection, a recent observational study found that low levels of vitamin D were not associated with getting the virus in the first place.
The study tested over 18,000 individuals ages 37 to 56 for anti-bodies indicating past infection with COVID-19. They compared these results to vitamin D levels that had been measured before the pandemic. After controlling for other factors, even extremely low vitamin D levels (under 20 nanograms per milliliter) were not associated with the presence of antibodies for the virus.
As we wrote in this section last month, the U.S. Preventive Health Service Task Force has determined raising vitamin D levels through supplementation has not been proven to improve health outcomes, and there is not enough evidence to recommend universal testing for vitamin D blood levels. This study adds to the body of information reviewed by the Task Force, suggesting vitamin D supplementation is not protective against COVID-19 infection, even in individuals who have low blood levels of this vitamin.