At present the only cure for food allergy is to avoid eating the food responsible for the allergy. Thus, food allergy or food hypersensitivity is a disease that is not only of concern to the individual who is affected but also to those involved directly and indirectly in supplying and preparing food for the food-allergic individual, and its impact on society should be evaluated on this basis. It is generally assumed that questionnaire-based studies vastly overestimate the prevalence of food hypersensitivity. The reported perceived prevalence of food hypersensitivity varies from 3.24% to 34.9%, which may be explained partly by the difference in reporting lifetime prevalence compared with point prevalence. However, of more importance is the apparent inverse correlation between response rate and prevalence (the higher the response rate, the lower the perceived prevalence). The three most-recent prevalence studies on food hypersensitivity (one on perceived food hypersensitivity and two on confirmed food hypersensitivity) all report estimates for prevalence of approximately 3%, but their criteria for including subjects as being positive are not identical, although they do overlap. Furthermore, because of differences in methodology there is no definitive information to indicate whether the prevalence of food allergy is increasing. However, the high prevalence of pollen-related food allergy in younger adults in the population suggests that the increase in pollen allergy is also being accompanied by an increase in pollen-related food allergy.