Patients hospitalized for covid-19 have low levels of vitamin D.

(CNN) – More than 80% of patients hospitalized for COVID-19 had a vitamin D deficiency, according to a small study from a hospital in Spain, but researchers found no relationship between vitamin D concentrations and COVID-19 severity. .

As this was an observational study, it is not possible to prove that low vitamin D levels cause severe COVID-19 in patients, nor that giving vitamin D to healthy people prevents it.

Researchers at Santander’s Marqués de Valdecilla University Hospital analyzed information from nearly 200 covid-19 patients hospitalized in March and compared it to the same number of people, matched by age and sex, without covid-19.

They found that 82 percent of COVID-19 patients were vitamin D deficient, compared with only 47 percent of controls, they reported in the Journal of Clinical Endocrinology & Metabolism.

Vitamin D is needed for normal cell function and bone health. Studies have shown that vitamin D deficiency affects the immune system.

It is not possible with any observational study to unravel cause and effect, and in this study it is even more so because many of the factors that make people prone to vitamin D deficiency, such as advanced age and health conditions such as high blood pressure : they are the same ones that put people at risk of suffering from severe covid-19.

This makes it difficult to determine the role of vitamin D in the prevention and treatment of covid-19.

But the study’s lead researcher said a supplement is worth trying. “Vitamin D treatment should be recommended in covid-19 patients with low levels of circulating vitamin D, as this approach could have beneficial effects on both the musculoskeletal system and the immune system,” said José Hernández. of the University of Cantabria.

“One approach is to identify and treat vitamin D deficiency, especially in high-risk individuals, such as the elderly, comorbid patients and nursing home residents, who are the main target population for COVID-19.”

The National Institutes of Health indicate on their website that the role of vitamin D supplements in the prevention or treatment of covid-19 is unknown, so they cannot “recommend either for or against the use of vitamin D for the prevention or the treatment of covid-19 “.