In the midst of the dark days of winter and the continuing COVID-19 pandemic, recent focus has been placed on the immunomodulatory role of vitamin D and its potential for influencing COVID-19 clinical outcomes. Low vitamin D is associated with increased likelihood of respiratory infections, but whether this impacts COVID-19 clinical progression is debatable.

A recent analysis by Lohia et al. assessed retrospective cohort data from 270 patients with COVID-19 infection and compared serum vitamin D concentrations with mortality, need for mechanical ventilation and admission to intensive care. Of these patients, 117 were male and 153 were female, more than half were aged 65 or older (n=139, 51.5%), the majority were African American (n=216, 80%) and more than a third had vitamin D levels below 20ng/ml (n=95, 35.2%). In the cohort and subgroup analysis, vitamin D levels showed no significant association with mortality, need for mechanical ventilation or admission to intensive care.

These data provide further insight, but the authors note that further studies are warranted before any conclusions can be made regarding any association between vitamin D status and clinical outcomes for COVID-19. Vitamin D is essential for good health and adequate intake via diet, supplementation and safe sunlight exposure along government guidelines are recommended to support bone and muscle health. Avoidance of vitamin D deficiency and adherence to COVID-19 guidelines remain the most robust approaches to minimising adverse risk to health (BMJ Nutrition, Prevention & Health doi:10.1136/bmjnph-2020-000089).

Read the full article in American Journal of Physiology doi:10.1152/ajpendo.00517.2020