Research differences on whether vitamin D could provide benefits during the COVID-19 Pandemic
Researchers know that groups that traditionally exhibit vitamin D deficiency are the only groups affected by COVID-19, including older adults and nursing home residents, and black, Asian and minority groups. It has also been made clear that more time spent indoors during the pandemic has limited people’s chances of getting physiological levels of vitamin D from sunlight.
A report from the National Institute for Health and Care Excellence (NICE) published in December 2020 reviewed recent studies on vitamin D and COVID-19. The recommendations support routine recommendations for individuals to supplement vitamin D to maintain bone and muscle health during the fall and winter months, but the study concluded that there is a lack of evidence to support use of vitamin D for COVID-19 inhibition.
The debate around vitamin D began long ago in the 1920s when researchers discovered that it stopped rickets. Researchers began exploring its potential uses in non-skeletal outcomes, including immune function, cardiovascular health, and cancer. However, despite clear evidence of the benefits of vitamin D in bone growth and maintenance, there is a lack of evidence that supports improvement in other health and disease processes.
In particular, speculative studies have suggested that vitamin D supplementation may improve the incidence of respiratory diseases, a finding that may affect COVID-19 pandemics; however, randomized trials have had mixed results.
A commissioned study from a randomized clinical trial in more than 20,000 adults in Australia found that monthly doses of vitamin D did not reduce the risk or severity of respiratory diseases. Although the results showed a statistically significant effect on the overall symptoms based on analysis of participants’ diary data, the reduction was only 0 to 5 days and was inconsistent with clinical significance.
Similarly, a systematic review and meta-analysis based on complete data from trials concluded that vitamin D fortification was safe and had little effect on immunity to respiratory infections. This effect was associated with daily doses of between 400 and 1000 IU of vitamin D for up to 12 months, although the researchers noted significant heterogeneity over trials.
The NICE report concluded that it is important to keep track of new evidence because it has been peer-reviewed and published, incorporating results from several ongoing clinical trials examining vitamin D results. and COVID-19. While health decisions should be based on clear evidence, COVID-19 emergencies may require different rules.
REFERENCE
Vitamin D and COVID-19: why the controversy? Lancet diabetes and endocrinology; 11 January 2021. https://www.thelancet.com/journals/landia/article/PIIS2213-8587(21)00003-6/fulltext#articleInformation. Accessed January 21, 2021.