Epidemiology of food allergy: what's new? A critical appraisal of recent population-based studies

To appraise critically recent unselected population-based studies to establish the "true" prevalence or incidence of subjective and objective food allergy, and of food sensitization.

Five recent studies in children (< 10 years), and one in adults (60-97 years) were identified. Three studies in children (UK and Denmark) applied thorough diagnostic assessments, confirming the overestimation of parent-perceived food allergy compared with objectively assessed diagnosis. A further study in 9-year-old children (UK) found that subjectively assessed food-related wheeze was five times as common in children of south Asian ethnicity than in white children, all born in the same region. A study from Thailand suggested that the prevalence of subjectively and objectively assessed food allergy in preschool children was lower than in western countries. A Hungarian study specifically examined food allergy in the elderly, a population until now neglected by food allergy researchers.

Based also on food challenge tests, valid estimates of the prevalence of food allergy in children up to 6 years were obtained in studies from the UK, Denmark, and Thailand. Two methodologically weaker studies highlighted issues, such as ethnic differences in food allergy and a high proportion of sensitization to food allergens in the elderly that urgently need further evaluation.