Vitamin D has long been known to be a major regulator for both the
endocrine and the immune system. With the advent of COVID-19 pandemic,
there has been a growing interest in looking at the feasibility of using
vitamin D as a preventative and therapeutic option in the management of
the disease. A low serum level of vitamin D is linked to higher
incidence of respiratory tract infection and disease progression.
Vitamin D supplementation has proven to be effective in enhancing the
immune system, strengthen lung epithelial barrier, and prevention of
unchecked inflammatory response. Previous studies on the roles of
vitamin D in managing influenza and other enveloped virus infection
could shed light on the possible roles of vitamin D in the current
pandemic. More randomised controlled trials are needed to explore the
effects of vitamin D supplementation on COVID-19 infection.