The External Exposome and Food Allergy

Abstract

Purpose of review: The recent increase in childhood food allergy prevalence strongly suggests that environmental exposures are contributing to food allergy development. This review summarizes current knowledge about the role of the external exposome in food allergy.

Recent findings: There is growing evidence that environmental exposure to food antigens in house dust through non-oral routes contributes to food sensitization and allergy. Co-exposure to environmental adjuvants in house dust, such as microbial products and fungal allergens, may also facilitate allergic sensitization. While a high-microbe environment is associated with decreased atopy, studies are mixed on whether endotoxin exposure protects against food sensitization. Several chemicals and air pollutants have been associated with food sensitization, but their role in food allergy remains understudied. Children are exposed to numerous environmental agents that can influence food allergy risk. Further studies are needed to identify the key early-life exposures that promote or inhibit food allergy development.

Keywords: Air pollution; Environment; Exposome; Exposure; Food allergy; House dust.

Figure 1.

Co-exposure to environmental peanut and adjuvants in house dust may promote sensitization and peanut allergy development. House dust contains both peanut protein and environmental agents with adjuvant activity, including microbial products (e.g. endotoxin, fungal cell wall components), protease allergens from house dust mite and fungi, and particulate pollutants. Co-exposure to environmental adjuvants may modify immune responses against peanut protein, resulting in allergic sensitization instead of tolerance.