It's well known that vaccines can cause temporary side effects, including fever. What's more surprising is that some people seem more susceptible than others to developing these side effects after vaccination. To understand what factors contribute to these individual differences, researchers from the Max Planck Institute and the Pasteur Institute, among others, analyzed the diet and gut microbiota of vaccinated individuals. Their results, published on October 8, 2026, in Science, Studies show that diet plays a role by altering the gut microbiota. This could be the cause of chronic inflammation, which amplifies the side effects of vaccines.
By Nicolas Gutierrez C. THE Subscribers
Mild side effects caused by some vaccines, such as fever and headaches, are thought to be exacerbated by the effect of ultra-processed foods on the gut microbiota.
Fever is one of the most common side effects after vaccination.
Photo by ANDERS WIKLUND / TT NEWS AGENCY / TT NEWS AGENCY VIA AFP
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