The level of peanut allergy in children has sharply decreased: what changed the rules.

According to Vox: If you, like me, are a parent of a small child, you are probably facing one of the most common fears. (And it's not 'Golden' from KPop Demon Hunters, though that's close too.)

It’s ordinary peanuts. Even if your child does not have a nut allergy, surveys show that about 4.5% of children in the U.S. have this allergy. This means parents have to constantly check lunches and snacks for even tiny traces of peanuts. The problem with peanut allergy has been worsening for a long time — self-reported prevalence of peanut or nut allergy among children in the U.S. tripled between 1997 and 2008.

However, there is good news now: Researchers at Children’s Hospital of Philadelphia (CHOP) conducted a comparison of peanut allergy cases and other food allergies before and after the changes in medical recommendations in 2017. They found that children are now diagnosed with significantly fewer food allergies. Compared to the data before the changes and after 2017, there was a significant reduction in food allergy cases - approximately 36%, including about a 43% reduction in peanut allergy.

“This is the prevention of a potentially life-threatening, life-changing diagnosis,” said Dr. Edith Bracchio-Sanchez, a pediatrician at Columbia University Irving Medical Center, to journalists from the New York Times.

What changed - and why it worked

For many years, the medical community advised parents to delay introducing allergenic foods into their children’s diets. In 2000, the American Academy of Pediatrics (AAP) presented a schedule recommending delaying the introduction of cow's milk until one year, eggs until two years, and nuts and fish until three years.

The idea of delaying the introduction of potentially allergenic foods seemed logical as a child's immune and gastrointestinal systems were not yet fully developed. Parents actively followed this recommendation.

However, in 2015, the LEAP experiment, which became the gold standard of randomized trials, showed that high-risk children who started eating peanuts early and continued to eat them in childhood had about an 80% lower risk of developing peanut allergy by age 5 compared to those who did not eat peanuts. Further studies confirmed that this protection persisted into the teenage years.

This shift underscores the value of early introduction of allergenic proteins such as peanuts, which toughen the immune system. The new recommendation encouraged parents to safely introduce peanuts within the first six months in forms suitable for children, such as diluted peanut butter or puffs, rather than whole nuts.

The results were a vivid example of the effectiveness of the healthcare system. Strong data prompted radical changes: the 2017 guidelines encouraged parents to introduce peanuts between 4 and 6 months. In 2021, a consensus document was prepared recommending the introduction of eggs and other allergens at the same age. This is a rare case where science clearly confirms the efficacy of recommendations.

New information about food allergies

The CHOP team analyzed electronic medical records related to the AAP, comparing data before and after the updated recommendations. Diagnoses of peanut allergy among infants decreased from 0.79% to 0.45%, and the overall number of IgE-mediated food allergies - from 1.46% to 0.93%. Impressively, peanut allergy became the second most common allergy, surpassed only by egg allergy, although the initial AAP recommendations solely focused on peanuts.

Researchers estimate that the changes have already prevented tens of thousands of cases - approximately 40,000 peanut allergies and about 60,000 overall food allergies since 2015. This is an impressive result, as all it takes is occasionally giving your 5-month-old peanut.

It is quite likely that over time even greater positive results can be achieved, as the effects of the new recommendations already indicate a significant positive trend. While only about 29% of pediatricians reported full implementation of the 2017 recommendations a few years ago, among allergists, these figures were higher. However, the significant decrease in allergies suggests the possibility of even greater changes as awareness and adherence to guidelines increases among doctors and parents.

This is more than just peanuts

Peanut allergies are indeed a serious problem. They usually last a lifetime, lead to numerous severe allergic reactions, and significantly impact everyday life — from school events to airplane flights. Preventing even a portion of new cases means fewer EpiPens in backpacks, fewer late-night calls to hospitals, and fewer hassles for families with allergies. There is also an economic dividend: annual costs of food allergies among children in the U.S. amount to about 25 billion dollars, or approximately 4,000 dollars for each affected child per year. By preventing the development of these allergies, one can significantly ease the financial burden for many years.

However, there is another important lesson for healthcare that goes beyond allergies. When a large and decisive trial demonstrates a specific outcome, radically change recommendations, communicate them clearly, and measure results in the real world. Close the implementation gap with clear guidelines for doctors, accessible materials for parents, and practical advice for high-risk families. Scientific expertise is now under threat like never before, and part of this criticism is warranted. But if you want to see an example of how the healthcare system can correct its approaches in light of new data, here is a vivid example laid out in a consumer-friendly form.

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