Main roads
-
Peanut allergy is one of the most common in the US and Canada
-
Researchers have discovered why people who are allergic to peanuts react so differently to them
-
They found that a type of bacteria called the gut Rotia helps stop the process that causes the reaction
MONDAY, July 20, 2026 (NewsDay News) – Why is a peanut allergy a life-and-death event for some people, but a minor inconvenience for others?
A new study shows that it can be applied to different populations of bacteria that colonize the mouth and gut.
“We found evidence that some of these microbes can help break down components of peanuts in ways that can affect allergic reactions,” the researcher said. Dr. Alberto Caminero Fernandezassociate professor of medicine at McMaster University in Ontario, Canada. “These findings point to a newly identified pathway linking the oral and gut microbiome to food allergy.”
Research – recently in The host cell and the microbe — shows how gut bacteria break down allergenic food components and affect a person’s response to peanuts in particular.
Peanut allergies are one of the most common allergies in Canada and the US. 2% to 3% of Americans have peanut allergies.
“Peanut allergy can cause serious reactions, such as difficulty breathing, and in some cases can even be life-threatening,” said the study’s co-author. Liam Rondoa postdoctoral fellow at McMaster’s Farncombe Family Health Institute, said in a news release. “However, some people with peanut allergies can eat small amounts without having a reaction. We were interested in why this happens.”
For the study, he and his colleagues examined saliva and colon samples from healthy volunteers. While they identified several types of bacteria capable of breaking down major peanut allergens, one stood out.
Types Rotia can limit the ability of peanut proteins to bind to antibodies – a process that occurs allergy reactions. Participants with more of these allergen-destroying bacteria were able to tolerate more peanuts before developing a reaction.
“These findings point to a newly identified pathway linking the oral and gut microbiome to food allergy, and they may help guide future work on prognosis and treatment,” Fernandez said.
The researchers confirmed their findings in a group of 120 children. Those who were more tolerant of peanuts Rotia.
They said these bacteria allow fewer peanut allergens to reach the bloodstream and reduce the activation of immune cells that cause the life-threatening allergic reaction, anaphylaxis.
The result: allergic reactions after exposure.
In Canada, where peanut allergy most commonly affects children, strict avoidance is the only way to manage it. About 1 in 3 children are exposed every year.
The researchers said their findings pave the way for new approaches in prevention and treatment, such as microbial or probiotic therapies as well as oral immunotherapy.
The study also included researchers from the US and Spain.
More information
Learn more at the Mayo Clinic peanut allergy.
Source: McMaster University, release, March 3, 2026
What does this mean for you?
New insights into how gut bacteria influence a person’s response to peanuts could lead to new treatments for peanut allergies.
