COVID: Vitamin D deficiency pre-infection may lead to severe corona case — JERUSALEM POST
Official study results showed that those with Vitamin D deficiency were 14 times more likely to have severe or critical cases of COVID-19.
“There is a clear connection between a deficiency of vitamin D and COVID-19 mortality and severity, according to researchers from the Azrieli Faculty of Medicine of Bar-Ilan University.
The study, published on Thursday in the journal PLOS ONE, was one of the first to study the levels of vitamin D prior to the infection of COVID.”
https://www.jpost.com/health-and-wellness/coronavirus/article-695495