More than 80% of COVID patients vitamin D deficient: study

This is the latest preliminary research on the role of vitamin D in COVID-19.

Diana Duong 3 minute read October 28, 2020
Close up of Vitamin D3 Omega 3 fish oil capsules on green background

A new, small study adds to a body of evidence of the role of vitamin D in COVID-19 infection. But larger studies are needed. Getty Images

More than 80 per cent of hospitalized COVID-19 patients at a hospital in Spain had a vitamin D deficiency, according to a new small study.

Published by the Endocrine Society, Spanish researchers from the University Hospital Marques de Valdecilla looked at the vitamin D levels of 216 patients admitted for COVID-19 between March 10 and 31. They compared their vitamin D levels to those of a control group of 197 people of similar age and sex from a control cohort in the same geographical area.

They found that of the 216 COVID-19 patients, 82.2 per cent had a vitamin D deficiency, compared to 47.2 per cent of the control group. It was also found that men had “especially lower” vitamin D levels than women.

The researchers also found vitamin D-deficient COVID-19 patients were more likely to stay in hospital longer and have an increased prevalence of hypertension, cardiovascular diseases, and higher iron levels in the body.

And while these findings are significant, researchers say that the number of participants who took supplements is still too small, making it hard to draw any solid conclusions from this study. They also say because it was only conducted on “a single Spanish tertiary-care hospital,” the findings might not apply to other settings, ethnicities or countries.

How’s your vitamin D?

With the potential for COVID-19 to continue its spread indoors during the colder months, and vitamin D harder to come by as the days become shorter, it may be time this winter to revisit whether you’re meeting your vitamin D needs, regardless, given its benefits for immune system function and our calcium levels.

“One approach is to identify and treat vitamin D deficiency, especially in high-risk individuals such as the elderly, patients with comorbidities, and nursing home residents, who are the main target population for the COVID-19,” said study co-author José L. Hernández, in a press statement.

“Vitamin D treatment should be recommended in COVID-19 patients with low levels of vitamin D circulating in the blood since this approach might have beneficial effects in both the musculoskeletal and the immune system,” he said.

What is a vitamin D deficiency?

Researchers of this particular study describe being deficient in vitamin D as having levels lower than 20ng/mL, which can be determined with a blood test. Not enough vitamin D can affect bone structure, leading to risks of thin, brittle bones and also affect the immune system’s ability to function.

Those most at risk of a vitamin D deficiency are those over 65 and people with dark skin. The darker your skin and the older you are, the less your body is able to produce the vitamin from the sun.

The Canadian government recommends 600 international units (IU) of vitamin D for adults every day. That increases to 800 IU for people older than 70 years, and 400 IU for infants.

You can also get vitamin D from what you eat, but diet may not be enough, which is why sun exposure or supplementation may be needed. But since the winter brings with it less sunlight, it may be helpful to focus on food sources of vitamin D such as milk, orange juice, cheese, and yogurt. The only natural food sources of vitamin D in Canada are fatty fish and egg yolks. | @dianaduo
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