A Spanish study found giving supplemental vitamin D3 to hospitalized patients with PCR-confirmed COVID-19 reduced ICU admissions by 82% and mortality by 64 percent. Vitamin D plays an important role in most diseases, including infectious disease, which is why from the very beginning of the COVID-19 pandemic, I suspected that optimizing vitamin D levels among the general population would significantly lower COVID-19 incidence and death. Since then, mounting evidence reveals this is indeed the case, as researchers have repeatedly demonstrated that higher vitamin D levels reduce rates of positive tests, hospitalizations and mortality related to this infection. Vitamin D3 Reduces COVID Infection and Mortality A now-retracted, preprint Spanish study found that giving supplemental vitamin D3 (calcifediol) to hospitalized patients with PCR-confirmed COVID-19 reduced ICU admissions by 82% and mortality by 64%. People who already had higher vitamin D at baseline were 60% less likely to die. Another study was published in …