TORONTO — A new study suggests a correlation between vitamin D deficiency and the risk of contracting COVID-19, though the authors believe further research is needed.
The study, published Thursday in the Journal of the American Medical Association, examined 489 people who had been tested for COVID-19 between March 3 and April 10 and had been tested for vitamin D deficiency in the year prior.
The results showed that 19 per cent of the vitamin D deficient people tested positive for COVID-19, compared to 12 per cent of the vitamin D sufficient people.
“The multivariable analysis suggests that persons who are likely to have deficient vitamin D levels at the time of COVID-19 testing were at substantially higher risk of testing positive for COVID-19 than were persons who were likely to have sufficient levels,” the researchers state.
The researchers do note there are several limitations to their research, including the idea that people with vitamin D deficiency typically have several of the other risk factors associated with COVID-19, including advanced age, obesity and diabetes.
“Observed associations of vitamin D with outcomes in almost any observational study may fail to accurately reflect any potential causal effects of vitamin D on outcomes,” the study notes.
“Nevertheless, our analysis controls for many of these factors, and the idea that adequate vitamin D levels could prevent COVID-19 is supported by the meta-analysis of randomized clinical trials.”
A similar study out of the U.K. found there was no statistical connection between COVID-19 risk and vitamin D, but those researchers used vitamin D data from between 10 and 14 years prior to the subjects’ COVID-19 testing, compared to the one-year timeline of the most recent research.
The researchers suggest their latest findings warrant clinical trials of vitamin D where subjects are given varying doses to understand how it may further impact the risk of COVID-19.
The connection between vitamin D and other respiratory illnesses is well known. According to the World Health Organization, vitamin D deficiency has been linked to pneumonia, tuberculosis and bronchiolitis.
Back in May, CTV News reported that researchers in Edmonton were preparing a study that would look at what, if any, benefit there would be in boosting vitamin D levels in the bloodstream of COVID-19 patients.
Other research out of New Orleans found 100 per cent of its sickest COVID-19 patients were deficient in vitamin D, while researchers in Ireland found COVID-19 deaths and infections are lower in countries where vitamin D is added to food or where people are encouraged to take vitamin D supplements, such as Finland and Norway.