One in Three Infants Misdiagnosed with Peanut Allergy, Research Reveals

A recent study indicates that a significant number of infants diagnosed with peanut allergies may not actually be allergic. Approximately 34.8% of infants who were suspected to have a peanut allergy did not react during a supervised oral food challenge, suggesting that a diagnosis based on medical history and allergy test results alone may be misleading.

Peanut allergies have become increasingly common in recent years, affecting an estimated 6.2 million children and adults in the United States. However, new findings published in the November 2026 issue of *The Journal of Allergy and Clinical Immunology* challenge the reliability of traditional diagnostic methods. The study highlights the importance of conducting oral food challenges, which involve administering small, controlled doses of peanuts to assess for allergic reactions under medical supervision.

The authors of the study argue that a history of reactions or positive allergy test results should not be the sole basis for diagnosing a peanut allergy. This is especially crucial as unnecessary treatments and dietary restrictions can put a strain on families. The suggested oral food challenge could help identify infants who do not require such interventions.

To thoroughly investigate this issue, researchers evaluated the Allergy Development to an Accelerated Path to Tolerance (ADAPT) program, which was implemented in 2024 at multiple children’s hospitals in Australia. This program employs a standardized approach to assess and treat infants suspected of having peanut allergies.

The study involved infants who had previously experienced mild to moderate reactions to peanuts before their first birthday and had shown signs of peanut sensitization through allergy testing. Medical records were analyzed to determine the accuracy of the program’s diagnostic methods and the safety of its treatment protocols.

During the oral food challenges, which involved administering doses ranging from 15 to 1,300 milligrams of peanut protein, medical teams carefully monitored the infants for any adverse reactions. Out of 778 infants who participated in these challenges, 507 exhibited allergic reactions, while 271 did not react at all, even though they had prior reactions and positive test results.

These results underscore a critical point: relying solely on medical history and allergy testing may lead to misdiagnosis. Of those who reacted, 61 infants experienced severe allergic reactions known as anaphylaxis, but these cases were managed effectively by medical staff.

The findings suggest that supervised oral food challenges could be instrumental in confirming peanut allergies before initiating treatment or imposing long-term dietary restrictions. Dr. Erin Banta, a board-certified allergist, emphasized the significance of these findings, stating that they could alleviate unnecessary burdens on families and guide appropriate treatment decisions.

Experts recommend that parents should not attempt to introduce peanuts to their infants at home without consulting a pediatrician or allergist. Instead, they should seek proper testing and consider a supervised food challenge to ensure safety.

The overarching message from this study is clear: not every positive allergy test indicates a true food allergy. An accurate diagnosis can help protect children while enabling those without allergies to enjoy a more normal, less restrictive diet.