The Role of the Indoor Exposome in Food Allergy Development

Due to the rapid rise in the prevalence of food allergy, environmental exposures, in addition to genetic susceptibility, are likely contributors to allergic disease. In developed countries, individuals spend a substantial proportion of time indoors. Therefore, the indoor exposome provides a unique framework to examine factors driving the increase in the rates of food allergy. This review summarizes epidemiological and mechanistic evidence of the indoor exposome, consisting of the combined exposures to food antigens, microbes, and chemicals encountered in indoor environments during early life, and their influence on food allergy development.

Indoor house dust contains detectable food allergens, which remain biologically active and may be linked to non-oral exposure, leading to allergic sensitization. In contrast, early-life exposures to diverse microbes and their products are associated with protection from allergic disease. Emerging evidence further demonstrates that indoor chemicals, including detergents, plasticizers, and pollutants, can disrupt epithelial barrier integrity or function as immune adjuvants, thus increasing susceptibility to food sensitization. Collectively, these findings highlight the indoor exposome as a complex and important determinant of food allergy risk. Improved understanding of how the indoor exposome influences food allergy development may inform future primary prevention or intervention strategies.