Researchers in Spain have discovered that 82% of hospitalized patients with Covid-19 were vitamin D deficient in a new study published today. They studied vitamin D levels in 216 patients admitted to the hospital for Covid-19 treatment in March this year, finding that 8 in 10 patients were considered clinically deficient. … However, it is important to point out that the conclusions of this study are correlative, not causative - meaning that it can’t be concluded that vitamin D deficiency was directly responsible for a higher chance of being hospitalized with Covid-19.