A cross-sectional study of the prevalence of food allergies among children younger than ages 14 years in a Beijing urban region

Background: The prevalence of food allergies has increased over the past several decades, but little is known about this issue in Beijing. Objective: The objectives of this study were to assess the prevalence of food allergies in the Beijing urban area and to summarize the clinical features and common food allergens in children <14 years of age. Methods: We conducted a cross-sectional study of children ages 0-14 years who were recruited from 10 kindergartens and 20 primary and middle schools in two communities in the central region (Xicheng district). After the administration of a screening questionnaire, those who reported symptoms of food allergies were interviewed for further diagnoses. All data were analyzed by using chi(2) tests. Results: Of the 13,073 enrolled children, 423 children (3.2%) were deemed by physicians to probably have food allergies. The boys exhibited a significantly higher prevalence than did the girls (3.6 versus 2.9%, respectively, p < 0.05). Among the children with probable food allergies, 58.9% reported skin symptoms, which were the most frequently occurring symptom type. Preschool age was the most common onset age for food allergies, with a rate (41.8%) that was higher than those for infants (27.1%) and school-age children (31.1%) (p < 0.01). Fruit was the most commonly reported food allergen (46.8%). Food allergies due to milk and eggs mainly occurred during infancy, and fruit allergies occurred in preschool- and school-age children. The seafood allergy prevalences were nearly the same across the three age groups. Conclusion: The total prevalence of probable food allergies in children <14 years of age in the Beijing urban area was 3.2%, and the prevalences were different between genders and among ages and foods. Skin symptoms were the most common manifestation. Fruit and seafood were the most common allergens.