Microbes to the rescue! Swallowing one common strain of bacteria could wipe out your worst food allergies, suggests a new study from American and Swiss researchers.
After the study team exposed peanut-sensitive mice to a variety of bacteria called Clostridia for five weeks, the rodents’ nut allergies all but evaporated. Simply put, their tiny bodies stopped producing inflammation-causing antibodies in response to peanuts. Even when the researchers stopped giving the mice the Clostridia bacteria, the whiskered, little test subjects still showed reduced sensitivity to peanuts, says study coauthor Taylor Feehley, a pathology researcher at the University of Chicago.
How is this possible? There are millions of bacteria in your stomach and intestines, which experts like Feehley call your “microbiome.” The types and amounts of these bacteria vary from person to person, and they serve all sorts of important functions, from aiding your digestion to bolstering (or harming) your immune responses, research has shown.
Food allergies have exploded in the US in recent decades, especially among children. What does this have to do with bacteria? The study authors point to the overuse of bacteria-killing antibiotics as one potential explanation. Basically, by wiping out certain strains of gut bacteria, antibiotics may render your immune system prone to overreaction when confronted with harmless dietary staples, like peanuts or dairy.
That’s the bad news. The good news is that this research indicates you can recolonize your gut with beneficial bacteria and potentially reverse your body’s habit of flipping out in response to food allergens, Feehley says.
The nitty-gritty: Clostridia cause your immune cells to produce a signaling molecule called interleukin-22, the study authors say. This molecule thickens the lining of your intestine, and so stops food allergens from making their way into your bloodstream.
Even better news: This allergy-allaying therapy might be as simple as eating a little of the right type of bacteria, Feehley says. (Past research has shown that swallowing another type of bacteria, Lactobacillus casei, can help calm inflammation among rheumatoid arthritis sufferers.)
Unfortunately, Feehley says these bacteria aren’t something you can buy today in any kind of food product or supplement. “We actually used a combination of 37 different Clostridia,” she explains, adding that it’s also not clear if human beings will respond as well as mice to these gut microbes. “We’re working on developing this as a therapy for people,” she says, “but that will take some time.”
While you wait for the health scientists to do their thing, you may want to eat more yogurt. Studies have shown cultured foods like yogurt or kefir are packed with probiotics, healthful bacteria akin to Clostridia. They may not fight off your allergies, but studies have linked them to stronger immune systems.