A new study brings hopeful news to parents navigating food allergies. Peanut allergies in children are on the decline and experts say early exposure is the key reason why.
Researchers at Children’s Hospital of Philadelphia (CHOP) found that national guidance encouraging parents to introduce food allergens earlier in life is having the desired effect. The findings were published on October 20, 2025, in Pediatrics, the peer-reviewed journal of the American Academy of Pediatrics (AAP).
“This is the first real-world evidence showing that national guidelines encouraging parents to introduce peanuts and other allergenic foods early in infancy are having their intended effect,” says David Hill, MD, PhD, attending physician with CHOP’s Division of Allergy and Immunology and senior study author, in an interview with Parents.com.
For many years, parents were told to delay introducing peanut products to infants. That guidance has now changed dramatically.
“Prior to 2000, it had routinely been recommended to delay the introduction of peanuts until the age of 2 to 3,” explains Beth Oller, MD, a family physician to Parents. “In 2008, the AAP withdrew the recommendation to limit earlier introduction of peanuts and stated the early ingestion at 4 to 6 months could help to prevent allergies to peanuts.”
A pivotal moment came in 2015, when the Learning Early About Peanut Allergy (LEAP) study revealed that infants with severe eczema or egg allergies who were exposed to peanut products between 4 and 11 months had an 81% lower risk of developing peanut allergies. The findings transformed allergy guidelines worldwide.
Today, pediatricians recommend that parents introduce major allergens, such as egg and peanut, as early as 4 to 6 months, provided the child has no prior allergic reaction history.
The CHOP team analyzed electronic records from more than 120,000 children seen in pediatric offices across several U.S. states, comparing allergy rates before and after the 2015 and 2017 recommendations took effect.
“We saw a steady and statistically significant drop in new peanut and other food allergy diagnoses after those recommendations went into effect,” Dr. Hill says.
The results are striking. Researchers found a 27% drop in new peanut allergy diagnoses among children ages 0–3 since the 2015 guideline changes, and a 40% drop since the 2017 update.
Peanut allergies, once the most common childhood food allergy, have now been surpassed by egg allergies, according to the data.
“For years we’ve witnessed the power of how training the immune system toward food proteins can turn off the allergic response,” says Inderpal Randhawa, MD, a board-certified allergist, pediatrician, and founder and CEO of the Food Allergy Institute in Long Beach, California. “The study confirms what our clinical outcomes have shown: the immune system is teachable. If you present food antigens early, consistently, and safely, the immune system learns tolerance instead of launching a defensive allergic response.”
