Prevalence and distribution of sensitization to foods in the European Community Respiratory Health Survey: a EuroPrevall analysis

Background
Reports of adverse reactions to foods are increasing, but there is limited information on the comparative prevalence of sensitization to food allergens using standardized methods. Methods: Sera from the ‘random sample’ of young adults seen during the second phase of the European Community Respiratory Health Survey were analysed for IgE against 24 foods using ImmunoCAP. Sera were tested on five food mixes, and subsequently on individual foods in each positive mix.

Results
Sera from 4522 individuals living in 13 countries were tested for at least one food allergen mix. Prevalence of sensitization to any of the 24 food allergens
ranged from 24.6% in Portland (USA) to 7.7% in Reykjavik (Iceland). With few exceptions, the relative prevalence of sensitization to different foods was similar in all countries. Sensitization rates to egg, fish and milk were each less than 1%, and the most common sensitizations are not represented in current commercial mixes. The prevalence of sensitization to foods was not related to that of sensitization to aeroallergens but was related to the geometric mean total IgE for the country.

Conclusions
Sensitization to foods is common but highly variable. The relative prevalence of sensitization to different foods is more consistent than would be expected by chance, suggesting that quantity of consumption of specific foods does not determine prevalence. The aetiology of food sensitization is only partly similar to that for aeroallergens but is related to local levels of total IgE. This may provide an important clue to the origins of food sensitization.