The Nuance
Vitamin D for Covid-19: New Research Shows Promise
Studies highlight potential life-saving benefits. But some experts aren’t convinced.
The study’s findings were significant — “spectacular” even, in the words of at least one expert commenter.
A team of doctors at Reina Sofía University Hospital in Córdoba, Spain, split 76 newly admitted Covid-19 patients into two groups. One group got the standard treatment at the time, which included a cocktail of antibiotics and immunosuppressant drugs. The second group got the same standard treatment — plus a drug designed to raise vitamin D levels in the blood.
Among the 26 hospitalized people who received standard care alone, fully half went on to the intensive care unit (ICU) because their disease had worsened. Two of them died. But among the 50 people who received the vitamin D treatment on top of standard care, only one person ended up in the ICU. None died.
In their study write-up, published in October in the Journal of Steroid Biochemistry and Molecular Biology, the Spanish researchers explained that their experiment was a “pilot” study that requires follow-up work. But they also pointed out that theirs is not the first piece of evidence linking vitamin D to a reduced risk for severe respiratory infection. Far from it.
“Vitamin D supports a range of innate antiviral immune responses while simultaneously dampening down potentially harmful inflammatory responses,” says Adrian Martineau, PhD, a clinical professor of respiratory infection and immunity at Queen Mary University of London.
“The evidence that low vitamin D levels are a risk factor for severe [Covid-19] disease is not definitive, but many lines of research suggest that this is likely.”
Martineau was not involved with the Spanish study, but he has published several papers on vitamin D for the treatment and prevention of viral infections. In a 2017 research review, which appeared in the journal BMJ, he and his co-authors concluded that taking a daily or weekly vitamin D supplement is associated with a reduced risk for respiratory…