The Potential Influence of Vitamin A, C, and D and Zinc Supplements on the Severity of COVID-19 Symptoms and Clinical Outcomes: An Updated Review of Literature

Abstract

Coronavirus disease-19 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 is an ongoing viral epidemic that originated in China in December 2019. To date, no specific treatment is available for COVID-19. However, several studies have reported the benefits of vitamins A, C, and D and zinc in critically ill patients and in those with various infections, including respiratory infections and sepsis. The objective of this review is to discuss the potential role of vitamin A, C, and D and zinc supplementation in enhancing immune response, and reducing the severity of symptoms, and mortality rate in patients with COVID-19. Several clinical studies have shown that different doses of vitamins A, C, and D and/or zinc supplements reduce the ventilator, length of intensive care unit stay, and mortality rate. Future randomized clinical trials are warranted to conclusively establish protocols for the optimal doses of vitamin A, C, and D, as well as zinc supplements for improved clinical outcomes in patients with COVID-19.