Food Allergen Introduction Patterns in the First Year of Life: A US Nationwide Survey

To describe current practices of egg and peanut introduction in US infants in light of the 2017 guidance from The National Institute of Allergy and Infectious Diseases and the 2021 consensus statement from the North American and Canadian allergy societies encouraging introduction of these foods as early as 4 to 6 months of age to prevent the development of IgE-mediated food allergies. The study aimed to describe: (1) timing of peanut and egg introduction; (2) how introduction of peanut and egg relates to the introduction of other common food allergens; (3) the most common formats of peanut and egg used for introduction; and (4) how often caregivers reported using commercial “early food allergen introduction products”.

The study included a US population-based sample of 3062 US caregivers with children between the ages of 7 months and 3.5 years who answered the survey administered between January 21, 2021 and February 15, 2021.

A survey was administered to a US-population via web and phone. Demographics and feeding practices, including age of introduction of the food allergen were collected in the survey. Comparison of variables across strata of interest was performed using survey-weighted χ-square statistics. Summary statistics to calculate weighted frequencies and proportions were performed on R 4. Study specific variables of interest adjusted for potential confounding variables were assessed by covariate-adjusted, survey-weighted logistic regression models.

Demographic measures of the respondents were representative of the general US population. The survey found that 17.2% of caregivers introduced peanut and 15.5% introduced egg before 7 months of age. Before 1 year of age, 58.8% reported introducing peanut and 66.4% introduced egg. Breastfeeding was associated with a greater likelihood of introducing peanut before 7 months but was not associated with early egg introduction. Peanut butter and scrambled egg were the most common formats provided in infancy. Introduction of at least 1 of the top 9 allergens was reported by 94.1% of caregivers before 7 months of age and by 48.1% of caregivers by 1 year. Only 2.5% of caregivers reported introducing all the top 9 allergens before 7 months of age. Of the other top 9 allergens, cow’s milk, wheat, and soy had the highest rates of introduction during infancy. Introduction of egg and peanut before 7 months of age was significantly associated with introduction of other common food allergens by 1 year. Only 3.1% of caregivers reported using commercial early introduction products at least once and use was associated with having a parent with a food allergy or having seen an allergist before peanut introduction.

Less than half of caregivers in the US are introducing peanut products to their children before 13 months of age, and early introduction of egg is more frequent than that of peanut. Caregivers who introduce peanut and egg earlier are more likely to introduce other allergens to their infants. When compared with 2016 data collected from the Feeding Infants and Toddlers Study, there has been a shift toward earlier introduction of both peanut and egg in the last 5 years, however, given the strength of the recently published guidelines for early introduction of both peanut and egg, early introduction of these foods is still suboptimal.

This study represents an important assessment of how well US pediatrician and allergist providers are implementing society guidelines for the prevention of IgE-mediated food allergies and how well this guidance is being followed by US caregivers. While this study shows us that early allergenic food introduction at both 6 months and 1 year of age has increased since publication of these guidelines, rates of IgE-mediated food allergy in US children continue to rise. Further investigation is needed to understand both provider and patient factors that may be preventing more widespread implementation of these guidelines.