According to a new retrospective study of people tested for COVID-19, there is an association between vitamin D deficiency and the likelihood of being infected with COVID-19.
“Vitamin D is important for immune system function and vitamin D supplements have previously been shown to reduce the risk of viral respiratory tract infections,” David Meltzer, professor of medicine at the University of Chicago and head of hospital medicine And the author of the study in Lead Says JAMA Network Open. “Our statistical analysis suggests that this may be true for COVID-19 infection.”
The research team looked at 489 patients whose vitamin D levels were measured within one year prior to COVID-19 testing. Patients who had vitamin D deficiency (defined as less than 20 mg per milliliter of blood) were nearly twice as likely to test positive for COVID-19 than patients who had adequate levels of vitamin D.
It is important for researchers to note that in study only two conditions have often been observed simultaneously; It does not prove work-cause. Meltzer and colleagues plan further clinical trials.
Experts believe that half of Americans are vitamin D deficient, a much higher rate seen in African Americans, Hispanics, and people living in areas such as Chicago, where exposure to sufficient sunlight in winter is difficult.
However, research has also shown that certain types of vitamin D tests do not detect the form of vitamin D present in the majority of African Americans – meaning those tests may misdiagnose vitamin D deficiencies. The present study accepted either test as a criterion.
COVID-19 is also more prevalent among African Americans, older adults, nursing home residents, and health care workers — populations that all have an increased risk of vitamin D deficiency.
“Understanding whether COVID-19 exposure to vitamin D deficiency treatment can be of great importance locally, nationally and globally,” Meltzer says. “Vitamin D is inexpensive, generally very safe to take, and can be increased widely.”
Meltzer and his team emphasized the importance of experimental studies to determine whether vitamin D supplementation could reduce the risk, and potential severity, of COVID-19. They also highlight the need to study what strategies might be most appropriate for vitamin D supplementation in specific populations.
The University of Chicago / Rush University Institute for Translational Medicine Clinical and Translational Science Award and the African American Cardiovascular Pharmacogenetic Consortium funded the work.
Source: Gretchen Rubin for University of Chicago