In this study, vitamin D levels and rates of vitamin D deficiency were measured in 62 patients diagnosed with COVID-19 and 80 healthy controls. The results showed that vitamin D levels were much lower in COVID-19 patients than in the healthy control group. The lowest vitamin D levels were found in the most severe cases. It was concluded that vitamin D deficiency is a risk factor for COVID-19, and supplementation could help prevent COVID-19 infections. Further details can be found in the study.
Ye et al.