CHICAGO - A Northwestern Medicine study shows coffee consumption and eating lots of vegetables may offer some protection against Covid-19.
Using data from the UK Biobank, researchers examined the associations between dietary behaviours measured in 2006-2010 and Covid-19 infections in March-December 2020, before vaccines were available.
They focused on diet factors and self-reported intakes of coffee, tea, vegetables, fruit, fatty fish, processed meat and red meat.
Among the 37 988 participants tested for Covid-19 and included in the study, 17 percent tested positive.
The researchers found that one or more cups of coffee per day was associated with about a 10 percent decrease in risk of Covid-19 compared to less than one cup per day. Consumption of at least 0.67 servings per day of vegetables cooked or raw, excluding potatoes, was associated with a lower risk of Covid-19 infection.
Processed meat consumption of as little as 0.43 servings per day was associated with a higher risk of Covid-19. Having been breastfed as a baby reduced the risk 10 percent compared to not having been breastfed.
Exact mechanisms linking these diet factors to Covid-19 are unknown.
"Coffee is a major source of caffeine, but there are also dozens of other compounds that may potentially underlie the protective associations we observed," said senior author Marilyn Cornelis, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine. "Associations with processed meat, but not red meat, point to non-meat factors."
Most Covid-19 research thus far has focused on individual factors assessed after a positive Covid-19 test.
The study, posted on the website of Northwestern University (NU) on Monday, has been published in the journal Nutrients.
Northwestern Medicine is the collaboration between Northwestern Memorial HealthCare and Northwestern University Feinberg School of Medicine, which includes research, teaching and patient care.
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