According to a large study, women taking omega-3 fatty acids, probiotics, multivitamins or vitamin D supplements are less likely to test positive for COVID.
The protective effects from these nutrients were modest but significant.
On the other hand, the study found that taking vitamin C, zinc, or garlic supplements had no beneficial effect on reducing infection risk.
Since the beginning of the pandemic, many celebrity doctors, via social media, have encouraged taking specific dietary supplements to prevent and treat coronavirus.
In the UK, shares in food supplements rose by 19.5 percent before the first national lockdown, with a 93 percent increased in sales of multivitamins and a 110 percent increase in sales of vitamin C.
In the USA, the sales of zinc supplements increased by 415 percent when COVID fears were at their height.
Nutrients such as vitamin C, vitamin D, and zinc are important for supporting the immune system but whether any particular supplement can reduce the risk of being infected by coronavirus is not evident.
Consequently, this study tracked 445 850 individuals for 3 months to find out whether taking dietary supplements would reduce the risk of contracting COVID-19.
The UK results showed that regular supplementation of vitamin D lowered the risk of SARS-CoV-2 infection by 9 percent,omega-3 fatty acids by 12 percent, multivitamins by 13 percent, and probiotics by 14 percent.
Taking supplements regularly was defined as a minimum of 3 times a week for at least 3 months.
Women of different ages and weights were the ones who benefited from taking these supplements but not men.
The protective effect for the participants in the US and Sweden was even higher.
Americans who were taking multivitamins had a reduced risk of COVID infection of 12 percent, probiotics 18 percent, omega-3 fatty acids 21 percent, and for vitamin D, 24 percent.
Swedes who were taking multivitamins had a reduced risk of COVID infection of 22 percent, probiotics 37 percent, omega-3 fatty acids 16 percent, and for vitamin D 19 percent.
The differences in the figures might be related to the fact that this study relied on self-reported information and self-reported dietary supplement usage.
Professor Sumantra Ray, Executive Director of the NNEdPro Global Centre for Nutrition and Health, commented:
“We know that a range of micronutrients, including vitamin D, are essential for a healthy functioning immune system.
This, in turn, is key to prevention of, and recovery from, infections.
But to date, there is little convincing evidence that taking nutritional supplements has any therapeutic value beyond maintaining the body’s normal immune response.”
“What’s more, this study wasn’t primarily designed to answer questions about the role of nutritional supplements in COVID-19.
This is still an emerging area of research that warrants further rigorous study before firm conclusions can be drawn about whether specific nutritional supplements might lessen the risk of COVID-19 infection.”
The study was published in the BMJ Nutrition (Louca et al., 2021).