Early Peanut Introduction in Babies: CHOP Study Halves Allergies

CHOP researchers analyzed electronic health records from over 120,000 children and report that earlier peanut introduction after 2017 guidance correlated with a 27% decline in peanut allergy and roughly a 36–38% drop in overall food-allergy diagnoses.

Researchers at the Children’s Hospital of Philadelphia (CHOP) reviewed electronic medical records for more than 120,000 children seen at dozens of U.S. pediatric practices. They compared diagnosis rates before and after the National Institute of Allergy and Infectious Diseases (NIAID) guidance in 2017 that encouraged earlier peanut introduction for infants at risk for peanut allergy.

The CHOP team reported a 27% reduction in peanut allergy diagnoses and about a 36–38% drop in overall food-allergy diagnoses during the study period. The paper, published in Pediatrics on Oct. 20, 2025, frames the results as real-world evidence that earlier feeding practices appear linked to fewer IgE-mediated food allergies (hives, vomiting, and in severe cases, anaphylaxis). The authors note eggs surpassed peanuts as the most common allergen in the dataset.

The shift to recommending early peanut introduction traces to the LEAP (Learning Early About Peanut Allergy) clinical trial, which found that exposing high-risk infants to peanut products between 4 and 11 months reduced peanut-allergy risk by about 81%. Background coverage and expert commentary summarize those findings and subsequent guideline updates — see LEAP findings and guideline updates and the ACAAI summary.

After LEAP, the NIAID updated guidance in 2017 to encourage earlier peanut introduction for at-risk infants. Guidance broadened in 2021 to recommend introducing peanut and other allergenic foods around 4–6 months for most infants.

Lead author Stanislaw Gabryszewski, MD, PhD (CHOP), said the data show public-health interventions are working to reduce IgE-mediated allergies and support continued education for families and clinicians about early introduction.

“These results back continued education for families and clinicians about early introduction,” — Stanislaw Gabryszewski, MD, PhD

Cherie Zachary, MD, president of the American College of Allergy, Asthma & Immunology (ACAAI), called the results “promising real-world evidence” that early peanut exposure can help the immune system develop tolerance; she and other experts note eggs may also be reduced by similar strategies. Experts emphasize never giving whole peanuts to babies due to choking risk.

Other specialists praised the trends but urged caution about attributing all declines to feeding changes alone. Susan Schuval, MD (Stony Brook Children’s Hospital) said the findings reinforce early introduction even though not all families have followed guidance.

The CHOP analysis is observational. It can show association but not prove causation. Key limitations noted by authors include:

• The study relied on electronic health records and diagnosis codes rather than detailed feeding logs, so individual infant feeding histories were not available.
• Data cover a period ending in early 2019 and do not capture effects of the 2021 guideline updates.
• Changes in coding practices, clinician awareness, access to care, or other environmental factors could have influenced diagnosis rates.

Authors and outside experts emphasize these caveats while calling the downward trend encouraging.

Public-health leaders view the CHOP findings as evidence that clinical trials like LEAP can translate into population-level benefits when guidelines are adopted. If earlier introduction helps the immune system learn tolerance, potential benefits include fewer lifelong food restrictions, fewer emergency visits for reactions, and lower costs for families and health systems.

However, because the study is observational, clinicians should continue careful screening and counseling for infants at higher risk.

Pediatricians and allergy groups recommend discussing plans to introduce allergenic foods with a child’s clinician, especially if the infant has severe eczema or an existing egg allergy. For most babies, introduce small amounts of peanut-containing foods — such as thinned peanut butter mixed with purees or specially formulated peanut puffs — when solids begin (often around 4–6 months).

Key safety notes:

• Avoid whole peanuts and large lumps because of choking risk.
• Continue peanut-containing foods regularly (about twice weekly) to help maintain tolerance.
• If you suspect a severe reaction, seek medical care; epinephrine is the first-line treatment for anaphylaxis.

Further parent-focused resources and clinician guidance are available from ACAAI and hospitals such as Lurie Children’s.

Research indicates that training tools and educational programs for pediatric practices improve clinician adherence to early-introduction guidance. Such resources help clinicians counsel families more consistently and may be one reason population diagnoses fell in the CHOP analysis; see reporting on new training tools from Northwestern.

Local pediatric care and public health: San Diego pediatricians and county public-health officials can use the CHOP study as evidence to strengthen education on early peanut introduction. Consistent messaging from well-baby visits to community clinics could help reduce new allergy cases and stabilize demand at local allergy clinics. Families with high-risk infants should be offered timely screening and counseling.

Impact on emergency care and costs: Fewer food-allergy diagnoses could mean fewer severe reactions and emergency-room visits in San Diego, easing pressure on emergency departments and reducing costs for families and the health system.

Schools, daycares and childcare providers: Districts and centers may review allergen-management policies in light of shifting allergy patterns. While vigilance remains essential for children with established allergies, prevention efforts could reduce the number of children requiring strict avoidance plans.

Equity and outreach: San Diego’s diverse communities may have variable awareness of early-introduction guidance. Tailored public-health outreach — including language- and culturally-appropriate materials about safe ways to introduce peanut products and when to seek medical advice — can help ensure broader benefit. Community clinics and WIC programs are potential partners.

Local research and next steps: San Diego hospitals and researchers could examine regional data to see whether similar diagnosis declines occur locally. Collaboration between pediatric practices, UC San Diego Health allergy specialists and San Diego County Public Health could track trends, identify gaps, and design targeted education or clinician-training programs.

Primary sources and further reading:

• CHOP news release on the study
• Coverage summarizing findings and context (Fox News)
• ACAAI commentary on early introduction
• National Peanut Board summary
• Reporting on practice tools and clinician training (Northwestern)
• Additional coverage and expert perspective (Allergic Living)
• Parent guidance and clinician resources (Lurie Children’s)

Reporting by Times Media Service; sources include CHOP, ACAAI, National Peanut Board, Northwestern, Fox News and Allergic Living.