Multivitamins, Omega-3, Probiotics, Vitamin D May Lessen Risk of COVID-19

But protective effects are only seen in women.

Using multivitamins, omega-3, probiotics, or vitamin D supplements can reduce the risk of testing positive for SARS-CoV-2, the virus responsible for COVID-19 infection – at least in women – indicates a large population survey, published online in the journal BMJ Nutrition Prevention & Health.

But taking one of the vitamin C, zinc, or garlic supplements was not associated with a lower risk of testing positive for the virus, the findings show.

Since the start of the pandemic, there has been strong support from celebrities for the use of nutritional supplements to ward off and treat COVID-19 infection, the researchers say.

In the UK alone, market share rose 19.5% in the period leading up to the first national lockdown on March 23 last year, with sales of vitamin C up 110% and multivitamin sales up 93%.

Likewise, zinc supplement sales rose 415% in the first week of March, at the height of COVID-19 fears in the US.

Dietary supplements may help support a healthy immune system, but whether specific supplements may be associated with a lower risk of developing SARS-CoV-2 is not known.

In an effort to close this knowledge gap, the researchers used adult users of the COVID-19 Symptom Study app to see if regular supplement users were less likely to test positive for SARS-CoV-2.

The app was launched in the UK, US and Sweden in March 2020 to capture self-reported information on the evolution of the pandemic.

Initially, it recorded the location, age and major health risk factors of its users. But as time went on, subscribers were asked to provide daily updates on a range of issues, including symptoms, coronavirus test results, and health care. People with no apparent symptoms were also encouraged to use it.

For the purposes of this study, the researchers analyzed information provided by 372,720 UK subscribers to the app about their regular use of dietary supplements in May, June and July 2020 during the first wave of the pandemic, as well as any coronavirus test results.

Between May and July, 175,652 UK subscribers took regular dietary supplements; 197,068 no. About two thirds (67%) were women and more than half were overweight (BMI of 27).

In total, 23,521 people tested positive for SARS-CoV-2 and 349,199 negative between May and July.

The use of probiotics, omega-3 fatty acids, multivitamins or vitamin D was associated with a lower risk of SARS-CoV-2 infection: by 14%, 12%, 13% and 9%, respectively, after taking into account potentially influential factors, including underlying conditions and regular diet.

No such effects were seen in those taking vitamin C, zinc or garlic supplements.

And when the researchers looked specifically at gender, age, and weight (BMI), the protective associations for probiotics, omega-3 fatty acids, multivitamins, and vitamin D were only seen in women of all ages and weights. No such clear associations were seen in men.

Despite some differences, the same overall patterns were reflected in both US (45,757) and Swedish (27,373) subscribers.

The equivalent figures for the US and Sweden were a reduced risk of: 18% and 37% respectively for probiotics; 21% and 16% respectively for omega-3 fatty acids; 12% and 22% respectively for multivitamins; and 24% and 19% for vitamin D supplements, respectively.

This is an observational study and as such cannot establish a cause. The researchers also acknowledge several limitations, including that the study relied on self-reported data and a self-selected group. Also, no information was collected on supplement doses or ingredients.

But while the effects observed were modest, they were significant, note the researchers, who argue for large clinical trials to formulate evidence-based therapeutic recommendations.

“We know that a range of micronutrients, including vitamin D, are essential for a healthy immune system. This, in turn, is key to preventing and recovering from infections.

“But to date, there is little compelling evidence that taking nutritional supplements has therapeutic value beyond maintaining the body’s normal immune response,” said Professor Sumantra Ray, executive director of the NNEdPro Global Center for Nutrition and Health. , which co-owns the magazine.

Moreover, this study was not primarily intended to answer questions about the role of dietary supplements in COVID-19. This is still an emerging area of ​​research that requires further rigorous study before any definitive conclusions can be made as to whether specific dietary supplements can reduce the risk of COVID-19 infection, ”he warns.

Reference: April 20, 2021, BMJ Nutrition Prevention & Health.
DOI: 10.1136 / bmjnph-2021-000250