Vitamin D and COVID-19: An Update on Evidence and Potential Therapeutic Implications

The COVID-19 pandemic created havoc in the whole world since 2019. It is an explosively spreading infectious disease in which the infectious agent enters the body through sneezing coughing touching etc. The primary site of infection is the respiratory system, and the various common symptoms are dry cough, fever, dyspnea, sore throat, nasal congestion, and loss of taste sensation. A majority of the patients experience diarrhea, vomiting, severe headache, and muscle pain. Many research have been undertaken to study the therapeutic implications of different elements in coronavirus infection. One such element of interest is vitamin D. There is evidence in the literature regarding the usefulness of vitamin D in severe acute respiratory distress syndrome (ARDS) and several respiratory diseases. As the site of infection in coronavirus infection is primarily the respiratory system, reviewing in detail the correlation of this vitamin with SARS-CoV-2 infection, is an area of keen interest. Thus, the aim of this article is to explore and describe in detail the relation between the two, with reference to levels of this vitamin in diagnosed subjects and a need for its supplementation in the management of coronavirus infection and also in the prevention of post-COVID-19 complications. The review concluded that Vitamin D has an immunomodulating function. Its deficiency may lead to severe respiratory illnesses including ARDS. Vitamin D levels affect the disease course in COVID-19 infection and proper blood concentration can reduce the severity of the symptoms as well as post-COVID-19 complications.