New study: Vitamin D supplements may not reduce COVID-19 risk

Nutritionist says people might need a vitamin D supplement during the coronavirus pandemic.

Much has been written about vitamin D and its link to lowering the risk of, preventing or easing COVID-19. A new study out of Canada, however, suggests taking this vitamin supplement has no effect on COVID.

Vitamin D is vital to maintaining healthy bones, but it also boosts your immune system. And, according to WebMD, there is “mounting evidence that links low levels of the vitamin to an increased risk of type 1 diabetes, muscle and bone pain, and, perhaps more serious, cancers of the breast, colon, prostate, ovaries, esophagus, and lymphatic system.”

A research study from 2016 suggests vitamin D supplements may help to protect against acute respiratory tract infections.

However, a Jan. 6 article published in the journal JAMA stated “research findings about vitamin D and COVID-19 have been mixed and sparse.” Additionally, the Mayo Clinic noted in a Jan. 29 FAQ that “there isn’t enough data to recommend use of vitamin D to prevent infection with the virus that causes COVID-19 or to treat COVID-19, according to the National Institutes of Health and the World Health Organization.”

The new genetic study, however, suggests vitamin D supplements may not protect against coronavirus infection or COVID-19.

Vitamin D can be found in the blood in two forms: bound to a protein or free-floating. The free-floating form is the one that matters most when talking about innate immunity.

The study, which was published on June 1 in the journal PLOS Medicine, by researchers at McGill University in Quebec, Canada, focused on genetic variants that are linked to increased vitamin D levels.

The researchers compared genetic variant data from 14,000 people who had COVID-19 with that of more than 1.2 people who didn’t.

They determined that people who were more likely to have higher levels of vitamin D did not have a lower risk for the coronavirus, hospitalization or severe illness from COVID-19. This suggests vitamin D supplements won’t protect you against COVID-19.

“If you feed somebody a vitamin D supplement, it doesn’t matter how much you change the bound amount,” said Martin Kohlmeier, a professor of nutrition in the Gillings School of Global Public Health at the University of North Carolina, “it’s how much you change the free amount that matters for innate immunity.”

The authors concluded these findings, “together with recent randomized controlled trial data, suggest that other therapies should be prioritized for COVID-19 trials.”

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