Infant Diet Recommendations Reduce IgE-Mediated Egg, Peanut, and Cow's Milk Allergies

Background: Meta-analyses of randomized controlled trials have found that introducing eggs and peanuts earlier during infancy reduced egg and peanut allergy risk. Hence, infant feeding advice has dramatically changed from previous recommendations of avoidance to current recommendations of inclusion of common food allergens in infant diets. Objective: To compare the prevalence of IgE-mediated food allergies at 1 year of age between 2 cohorts, before and after infant feeding and allergy prevention guidelines changed. Methods: In cohort 1 (506 infants born 2006-2014), no infant feeding advice was provided to participants. In cohort 2 (566 infants born 2016-2022), when the infants were 6 months of age, all families were provided with updated infant feeding and allergy prevention guidelines. All infants had a first-degree relative with a history of allergic disease. At 1 year of age, infant food allergen sensitization and IgE-mediated food allergy were assessed. Results: Peanut, egg, and cow's milk were introduced earlier in cohort 2 than in cohort 1 (all P < .001). The combined prevalence of IgE-mediated peanut, egg, and/or cow's milk allergies was 4.1% in cohort 2 compared with 12.6% in cohort 1 (adjusted odds ratio [aOR]: 0.28, 95% confidence interval [CI]: 0.16-0.48, P < .001). Specifically, the prevalence of peanut allergy was 1.1% versus 5.8% (aOR: 0.24, 95% CI: 0.08-0.76, P = .015), egg allergy 2.8% versus 11.7% (aOR: 0.23, 95% CI: 0.12-0.45, P < .001), and cow's milk allergy 0.5% versus 2.4%, respectively (aOR: 0.14, 95% CI: 0.04-0.55, P = .005). Conclusion: Direct provision of updated food allergy prevention guidelines to families facilitated earlier introduction and reduced the prevalence of IgE-mediated peanut, egg, and cow's milk allergies.