A new study, published online last week in The FEBS Journal, has found that low vitamin D has emerged as a potential risk factor for COVID-19 and hospitalization.

Researchers found that participants who tested positive for COVID-19 were 50% more likely to have low vitamin D levels.

Senior author of the study Milana Frenkel-Morgenstern of Bar-Ilan University in Ramat Gan, Israel, told Medscape Medical News the findings suggest that clinicians should “test patients’ vitamin D levels and keep them optimal for the overall health, as well as for a better immuno-response to COVID-19.”

Some studies have been evaluating the potential role of vitamin D in preventing or minimizing the severity of COVID-19 infection.

In a video report, Dr. JoAnn Manson of Harvard Medical School in Boston referred to an observational study that found seriously ill COVID-19 patients had lower vitamin D levels, with other “compelling evidence” suggesting a strong link.

Frenkel-Morgenstern and her team looked at more than 7,800 people, of whom over 10% were COVID-19 positive. They examined electronic health records for demographics, potential confounders, and prognosis from February 1 to April 30.

The researchers found that nearly 90% of COVID-19 positive patients had low plasma vitamin D concentrations compared to 85% of participants who tested negative for COVID-19.

“Severe social contacts restrictions that were imposed on all the population and were even more emphasized in this highly vulnerable population” could explain these findings, the team noted.

They added, “We assume that following the Israeli Ministry of Health instructions, patients with chronic medical conditions significantly reduced their social contacts” and thereby reduced their infection risk.

In addition, the team found that most participants with vitamin D deficiency were more likely to be hospitalized for COVID-19 infection.

Moving forward, Frenkel-Morgenstern and her team will “try to decipher the potential role of vitamin D in the prevention and/or treatment of COVID-19” through additional studies.

Dr. Wayne Jonas, executive director of Samueli Integrative Health Programs, told Medscape Medical News, “This is a strong study — large, adjusted for confounders, consistent with the biology and other clinical studies of vitamin D, infections and COVID-19.”

He added, however, “The study makes a compelling case for possibly screening vitamin D levels for judging risk of COVID infection and hospitalization and the compelling need for a large, randomized vitamin D supplement study to see if it can help prevent infection.”

Dr. Jonas, who was not part of the study, continued, “Given that vitamin D is largely safe, such a study could be done quickly and on healthy people with minimal risk for harm.” The article originally appeared on Medscape Medical News.