The Role of Vitamins on the Prevention and/or Treatment of COVID-19 Infection; a Systematic Review

Background: Vitamins had been reported repeatedly as important micronutrients, on immune system. Objectives: In this study roles of vitamins on immune system were discussed in detail, as well as their probable roles on the prevention/ treatment of viral infections including COVID-19 infection. Method: Totally, 57 articles had been extracted from common indexing databases/websites, which were then classified to different maingroupsandsubgroups. The roles of Vitaminsonthe prevention and/or treatment of COVID-19 infectionhadbeenalso reviewed, and finally their contents had been purified and listed into different categorizations. Moreover, differential percentages of each vitamin related studies, differential percentages of studiesonthe association with COVID-19, andmechanismsof the vitamins effects on immune system had been reviewed for each vitamin. Results: In this study, the reviewed articles had been categorized into 5 main vitamin groups and 7 subgroups for vitamin B family groups. The most studied vitamin group was identified to be the B vitamins group followed by the vitamins A, D, and E groups that were ranked in next steps, respectively. However, in individual comparison of vitamins, vitamin A had been identified as the vitamin with maximum number of studies. Accordingly, more than half of these studies (66.66%) had focused on the immune-modulatory effects of vitamin D on the prevention and/or treatment of COVID-19 infection. Conclusions: Briefly, this study showed that, among all vitamins, roles of vitamin A, C, D, and E are more defined and maybe more effectiveonimmunesystem, which emphasizesonthe importance of vitamins in prevention of several viral infections like COVID-19. Therefore, sufficient vitamin intake can be recommended to prevent viral infections like COVID-19 infection.