A major shift in medical advice on introducing food allergens to infants appears to be paying off, with new research showing a significant drop in peanut allergies among American children.
According to a study published in the journal Pediatrics, roughly 60,000 children in the United States have avoided developing peanut allergies since 2015, when medical guidelines began recommending that babies be introduced to peanut-containing foods as early as four months of age. The new approach, which aligned U.S. policy with European standards, reversed decades of previous advice that urged parents to delay introducing such foods.
Dr. David Hill, an allergist and researcher at the Children’s Hospital of Philadelphia, said the findings mark a major success in allergy prevention. “I can actually come to you today and say there are fewer kids with food allergy today than there would have been if we hadn’t implemented this public health effort,” Hill said.
The research team examined health data from dozens of pediatric practices across the country, tracking food allergy diagnoses before and after the introduction of the new guidelines. They found that peanut allergies in children up to age three dropped by more than 27 percent after the 2015 recommendations for high-risk infants and by over 40 percent after the guidelines were expanded in 2017 to include all children.
Peanut allergy occurs when the immune system mistakenly identifies peanut proteins as harmful, triggering symptoms that can include hives, respiratory distress, and even life-threatening anaphylaxis. For years, experts believed delaying exposure could help prevent these reactions. However, the landmark 2015 LEAP (Learning Early About Peanut Allergy) trial led by Professor Gideon Lack at King’s College London overturned that view. The study found that introducing peanut products to infants dramatically reduced the risk of developing peanut allergies by more than 80 percent, with protection lasting well into adolescence.
Despite the evidence, adoption of the new guidance was initially slow. Some parents and health professionals were uncertain about how to safely introduce allergens outside clinical trials. Hill noted that updated recommendations issued in 2021 clarified the process, encouraging parents to introduce peanuts and other allergenic foods between four and six months without the need for prior testing.
“It doesn’t have to be a lot of food,” Hill said. “Small tastes of peanut butter, milk-based yoghurt, soy-based yoghurts, or tree nut butters are simple, safe ways to expose the immune system early on.”
The findings offer a hopeful sign that early exposure to allergens could help reduce food allergies on a population level—transforming what was once a life-threatening childhood condition into a largely preventable one.
