Although many people with dietary allergies experience mild symptoms when exposed to triggering foods, some face potentially fatal consequences. A bacterial compound called butyrate that’s made by healthy microbiomes has shown promise against allergic reactions in lab tests, but it’s nasty to take orally. Today, scientists describe a more palatable way to deliver this compound and report that their “polymeric micelles” are effective against peanut allergies in mice. The treatment could someday counteract many types of food allergies and inflammatory diseases.