"Vitamin D deficiency, associated with deleterious effects on innate and adaptive immunity, has many small but growing datasets that satisfy all of Hill's criteria as a risk factor for severe COVID-19."
"When deaths were evaluated on the basis of vitamin D deficiency (serum 25-OH-D <20 ng/mL), the fatality rate was 21%, compared to only 3% for those with higher levels. More striking was that vitamin D deficiency was found in 97% of severely ill patients who required ICU admission but in only 33% of asymptomatic cases, suggesting that low levels are a necessary component of severe COVID-19. This is one of numerous studies this year establishing the correlation of low vitamin D levels with an aggravated course of COVID-19, as a meta-analysis by Pereira and colleagues reveals."
"It is our responsibility as physicians not to wait for perfect evidence when making life-and-death decisions. Given the safety profile of vitamin D, the 40% prevalence of vitamin D deficiency in the U.S., and the fact that this season will likely be the deadliest phase of the pandemic to date, we need to act now. Identifying and eradicating vitamin D deficiency with early and aggressive supplementation in COVID-19 has the potential to save thousands of lives and should be one of our highest public health priorities."
John Umhau MD MPH
January 5, 2021
In an Open Letter addressed to key decision makers and health care workers, experts have laid out the research to recommend Vitamin D intake for adults up to 4000 IU (100mcg) daily. Those at an increased risk of deficiency due to excess weight, dark skin, or living in care homes may need higher intakes. Testing can help to avoid levels too low or high.
"The data strongly suggests that vitamin D is the safest, easiest, and most important anti-pandemic measure the world is failing to prioritize," says Karl Pfleger, Ph.D., biotech investor, former Google data scientist, and one of the organizers of VitaminDforAll.org.