“This study was the first to demonstrate that a microbiome-based therapy may improve food allergy in people while also revealing how gut bacteria, their metabolites and the immune system work together to influence treatment response,” Rachid says. “Larger studies of fecal and microbiota transplantation are now essential to confirm these findings, identify the patients most likely to benefit and discover beneficial bacteria that could be developed into targeted probiotic therapies for food allergy.”

Of the most common food allergy triggers, peanuts and tree nuts cause the most severe, life-threatening allergic reactions. Certain antibody medications or small-dose exposure immunotherapy can raise tolerance to a sensitive food, but allergic reactions soon recur once the therapy stops. Even if taken as prescribed, patients still may experience life-threatening allergic reactions, sometimes in response to the treatments.