To the Editor: Reported adverse reactions to food, which are common in many developed countries, can be produced by a wide variety of mechanisms. However, a low proportion of these are true food allergies.1 Recent Australian data show an increase in hospital presentations for food-induced anaphylaxis,2,3 but there are no Australian population data on the prevalence of either food allergies or adverse reactions to foods. Waiting lists for allergy services continue to remain long, and it is not known whether this is due to an increase in the prevalence of true food allergy or simply an increase in perceived food allergy.

In October 2007, we undertook an Internet-based survey to assess the prevalence of self-reported perceived food allergies in Australian households. Participants were drawn from a consumer research panel of 8385 people (solicited through Internet-based marketing) who were proportionally representative of the Australian population with respect to age, sex and state. Cohort members were invited to participate in an Internet-based “health survey”, with no mention of food allergy during recruitment. Within 24 hours we had 1386 respondents and the required quota of participants was deemed to have been reached.

Of the 1386 respondents, 406 (29.3%) reported at least one household member who believed he or she had a food allergy (Box). Of these, 250 (61.6%) reported at least one doctor-diagnosed allergy and 56 (13.8%) reported that the allergy was allergist-diagnosed. In addition, 42 respondents (3.0% of all respondents) reported that the person with the allergy had an EpiPen (Dey, LP, Napa, Calif, USA).

Although there will be some selection bias in our sample because people without Internet access could not be sampled, we believe this bias is likely to be low, as at least 64% of the Australian population currently has home access to the Internet.4

Our questionnaire did not attempt to distinguish between true food allergy, sensitisation to foods, food intolerance or adverse reactions to food, although the majority of allergies had been diagnosed by a doctor or allergist, and foods such as peanut are more likely to be associated with allergies than intolerances. The high rate of perceived allergy to fruit and vegetables in an Australian context was surprising, although allergic reactions to fruit and vegetables are well documented.5 This may reflect either a rising prevalence of birch-pollen syndrome, as has been reported in Europe,6 or a community poorly informed about the true nature of food allergy reactions.

Our data add to the evidence that there may be an increasing, largely unmet demand for health care information for patients with adverse reactions to food, including allergies. More formal evaluation should be undertaken to assess the type and prevalence of food allergy in the Australian context in order to facilitate future workforce planning and better community education.