The kidneys produce the hormone vitamin D. It controls blood calcium concentration and affects the immune system.
Vitamin D deficiency has been linked to a variety of health concerns, but research continues to examine why it affects other systems of the body. There are many studies that point out how beneficial vitamin D is on the immune system and how it offers protection against infections, in particular.
Mayo Clinic infectious disease specialist Dr. William F. Marshall wrote that not enough data exists to recommend the use of vitamin D to stop the infection from the coronavirus, which causes the disease COVID-19, or to treat COVID-19, according to the National Institutes of Health and the World Health Organization.
Multiple studies have reviewed vitamin D’s impact on COVID-19, according to Mayo Clinic.
A study of 489 people discovered those who were deficient in the hormone were more likely to test positive for the coronavirus than those who had normal vitamin D levels.
A small, randomized study saw that only one of 50 people hospitalized with COVID-19 who were administered a high dose of a type of vitamin D, calcifediol, required treatment in the intensive care unit. That’s compared to the group of 26 people who were not given calcifediol in which 13 of them had to be treated in the intensive care unit.
While vitamin D deficiency is common in the U.S., Black and Hispanic people are especially deficient in the hormone, according to a 2014 study. The two groups have also been disproportionately affected by COVID-19.