Does Vitamin D3 Improve Survival of COVID-19 Patients?

Ever since the start of the pandemic, doctors have been looking for ways to improve survival of COVID-19 patients. They have explored several different treatments with varying results. Now two studies examine the effects of vitamin D3, a compound known to have a powerful effect on the immune system.

In Spain, Vitamin D3 Improved Survival of COVID-19 Patients:

Investigators at the Hospital del Mar in Barcelona, Spain, report on a study of 930 COVID patients admitted to their facility (Preprints with The Lancet, Jan. 22, 2021). Roughly half of these patients were assigned to vitamin D3. In contrast, the remainder did not get the supplement, although other aspects of treatment were similar.

The protocol was somewhat unusual. It called for 532 micrograms (21,280 IU) of calcifediol (oral 25-hydroxyvitamin D3) on the first day. Subsequently, patients took 266 mcg (10,640 IU) on days 3, 7, 15 and 30.

The results were striking when it comes to severe illness and survival of COVID-19 patients. About 5% of those getting vitamin D required intensive care, compared to 20% of those who did not. In addition, 6.5% of the vitamin D recipients died, in contrast to 15% of the control group.

The researchers conclude:

“In patients hospitalized with COVID-19, calcifediol treatment at the time of hospitalization significantly reduced ICU admission and mortality.”

Can We Trust These Results Regarding Survival of COVID-19 Patients?

The study has not yet been peer reviewed, and some COVID researchers are skeptical. They suggest that the statistical analysis used is incompatible with the randomization method. In fact, the preprint server has taken the publication down pending investigation of these questions.

High-Dose Vitamin D3 Did Not Shorten Hospital Stays in Brazil:

Further research will be essential. This week, researchers in Sao Paulo, Brazil, published their study of vitamin D3 for COVID-19 patients (JAMA, Feb. 17, 2021). This randomized clinical trial included 240 hospital patients with COVID-19. The scientists designed it to test the hypothesis that a single mega-dose (200,000 IU) of vitamin D3 would increase blood levels of 25-hydroxyvitamin D and shorten hospital stays. 

The investigators were careful to use random computer generated codes to randomly assign half of the patients to take that big dose of vitamin D3 dissolved in peanut oil. The other half took peanut oil alone. According to the investigators, “The solutions were identical in color, taste, smell, consistency, and container.”

The study focused on length of hospital stay, but the researchers also collected information on survival of COVID-19 patients, admission to the ICU and need for ventilators. There were no significant differences between the groups on any of these measures. Even when the scientists took initial vitamin D deficiency status into account, they did not find meaningful differences. They concluded that their study does not support the use of vitamin D3 in treating moderate to severe COVID-19.

Learn More:

If you are interested in utilizing vitamin D3 for more mundane purposes, you can learn a good bit about dosing, advantages and potential side effects from our eGuide to Vitamin D and Optimal Health.