Although in some countries the vaccine is well underway, many of us are still living in the midst of the risks of the unprotected COVID-19 pandemic and need all the help we can get.
An interesting study by an international team of researchers has found a small association with the use of supplements, which indicates fewer COVID-19 infections in women taking certain types of vitamins. But don’t rush to the pharmacy yet.
First, it is important to remember that the potential merits of multivitamins are extremely limited. In general, doctors advise that most people have enough micronutrients in their diet to stay healthy, and in the past, studies on the health benefits of vitamin supplements without diagnosed deficiency have been a real bag. mixed.
Despite this, in the early days of the pandemic, vitamins were one of the many items flying off the shelves of pharmacies.
“The UK supplement market rose 19.5 per cent in the run-up to the national‘ lockdown ’in early March 2020, with a 110 per cent increase in vitamin C sales and a 93 per cent increase percent in sales of multivitamin supplements, ”the team wrote. .
“Similarly, sales of zinc supplements increased 415 percent during the 7-day period that ended March 8, to the highest concentration of COVID-19 in the U.S.”
Supplements can play a role in supporting our health. Zinc is one of the few micronutrients related to shortening the course of common cold disease; those on vegan diets are advised to take vitamin B12 to help combat the deficiency. But avoiding infections is where it’s tricky.
The researchers took data from an app launched by health science company Zoe in early 2020 called the “COVID-19 Symptom Study app,” which asked participants a wide range of questions, including whether they used vitamins as probiotics. , garlic, fish oils, multivitamins, vitamin D, vitamin C or zinc. They also asked if they had been tested for SARS-CoV-2 and what the results were.
A total of 445,850 subscribers from the UK, US and Sweden had completed the questionnaire by July 31, 2020, providing the team with plenty of data to analyze.
In the UK, where the vast majority of respondents relied, just under half took some sort of supplement. About 6% of those who took supplements tested positive for SARS-CoV-2, while 6.6% of those who did not take supplements tested positive. This is a difference of about 2,500 people.
“In the UK cohort, users who supplemented their diet regularly with multivitamins had a lower risk of testing positive for SARS-CoV-2 by 13 per cent, while vitamin D had a lower risk of 9 per cent. percent, and probiotics had a 14 percent lower risk and with omega-3 fatty acids they had a 12 percent lower risk, ”the researchers wrote.
“There were no significant associations in those supplementing with zinc, vitamin C or garlic.”
There are many warnings to keep in mind here. First, it is an observational study based on self-reports, meaning that there is no causal evidence that vitamins result in fewer diagnoses of COVID-19.
The team adjusted for age, gender, BMI, and several other factors, and tried to account for the “bias of healthy users,” which is the idea that those who take vitamins are probably also healthier in other ways, which which could confuse the results.
Even after that, the results were still there, but interestingly, once the team divided the results by sex, for men there was no difference related to supplements, while in women the results were present at all ages and BMI groups.
The results were also slightly different between the U.S. and Sweden, finding that omega-3 supplements did not appear to help Swedish women, and probiotics and vitamin D appeared to help U.S. men.
“In the largest observational study on the use of dietary supplements and SARS-CoV-2 infection to date in more than 400,000 users of applications from three different countries, we show a significant association among users of dietary supplements. ‘omega-3 fatty acids, probiotics, multivitamins or vitamin D and lower risk of testing positive for SARS-CoV-2 infection,’ ”the team wrote.
“Women who purchase vitamins may also be more health-conscious than men, such as increased use of wearing face masks and washing their hands. In fact, in our data, we found that women used to wear masks. more often than men. “
After all this, the results show a very modest difference; for example, taking vitamins only reduced the absolute risk of obtaining COVID-19 by less than 1 per cent in UK study participants.
But at the population level, even small percentage points can save lives, so it’s imperative to find out if it’s really the vitamins that make the difference.
Researchers have called for a large clinical trial to test for potential effects in a more controlled environment. For now, if you’ve still received a vaccine, masks, good hygiene, and social distancing are likely to keep you much safer than any vitamin.
“This study was not primarily designed to answer questions about the role of nutritional supplements in COVID-19,” says Sumantra Ray, a Cambridge nutritionist who did not participate in the study.
“This is still an emerging area of research that requires a more rigorous study before firm conclusions can be drawn about whether specific nutritional supplements could decrease the risk of COVID-19 infection.”
The research has been published in BMJ Nutrition Prevention & Health.