Impact of vitamin D on COVID-19 and other viral diseases.

This editorial aims to elucidate the intricate relationship between vitamin D and viral pathogenesis. It explores the anticipated role of vitamin D as a modulator in the immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other viral pathogens. The editorial comments are based on the review article by Engin . The potential role of vitamin D in modulating immune responses has been highlighted by several studies, suggesting that it may influence both the risk and severity of infections. Vitamin D receptors are present in immunocompetent cells, which indicates that vitamin D can potentially modulate innate and adaptive immune responses. This context is relevant in the pathophysiology of coronavirus disease 2019 (COVID-19), where the immune response to the virus can significantly impact the disease progression and outcome. The immunomodulatory effects of vitamin D can protect against SARS-CoV-2 infection by enhancing innate and adaptive immune responses. It also maintains the integrity of the body's physical barriers and modulates inflammatory responses, thereby preventing entry and replication of the virus. Many studies have suggested that adequate vitamin D levels help alleviate morbidity and mortality associated with COVID-19. Furthermore, vitamin D supplementation has been linked with a lower risk of severe disease and mortality in COVID-19 patients, particularly in those with a deficiency during seasons with less sunlight exposure.