Food allergies in adults are over-reported, says study

Half of the reported food allergies amongst adults are not food allergies at all, says a new study from Germany.

According to a paper published in the journal Deutsches Ärzteblatt International, between 10 and 20 per cent of people see themselves as suffering from a food allergy, but the real figure may be half this.

Cornelia Seitz from her co-workers from Wurzburg University report that, of the 419 people with suspected food allergies tested in their study, less than 50 per cent actually had a IgE-mediated food allergy.

The findings show the importance of accurate diagnosis of food allergies, since a non-existent food allergy can lead to needless dietary restrictions. On the other hand,

As a results of growing numbers of people with reported food allergies, the "free-from" food market has been enjoying sales growth, with of over 300 per cent reported in the UK since 2000, according to market analyst Mintel.

The most common food allergen ingredients and their derivatives are cereals containing gluten, fish, crustaceans, egg, peanut, soybeans, milk and dairy products including lactose, nuts, celery, mustard, sesame seed, and sulphites.

Study details

Seitz and her co-workers recruited 419 people referred to an outpatient clinic for a suspected food allergy. The researchers tested for the presence of an IgE-mediated food allergy: Immunoglobulin E (IgE) is the predominant antibody associated with an allergic response.

Just over 50 per cent of the patients were found to have an IgE-mediated food allergy, report the researchers. Approximately half of these people had already experienced food-induced anaphylaxis, they added.

However, in the other patients, no IgE-mediated food allergy was found.

“The patient cohort presented in this study came from a university hospital. In 50 per cent of patients who reported a corresponding medical history, a food allergy was detected,” wrote Seitz.

“In the other 50 per cent, food allergies were mostly ruled out and exclusion diets therefore became unnecessary,” they concluded.

Growing concerns across the Atlantic

A recent reported called “Food Allergy Among US Children: Trends in Prevalence and Hospitalizations” from the Centers for Disease Control and Prevention showed a worrying rise in the number of young people with a food or digestive allergy in the United States.

The CDCP report found that eight types of food account for 90 percent of all food allergies: milk, eggs, peanuts, tree nuts, fish, shellfish, soy, and wheat.

The Food and Drug Administration (FDA) said recently that advisory labelling of allergens in food “may not be protecting the health of allergic consumers”.

The FDA is currently developing a long-term strategy to assist manufacturers in using allergen advisory labelling that is “truthful and not misleading, conveys a clear and uniform message, and adequately informs food-allergic consumers and their caregivers”.

Source: Deutsches Ärzteblatt International2008, Volume 105, Number 42, Pages 715-723“Food Allergy in Adults: An Over- or Underrated Problem?”Authors: C.S. Seitz, P. Pfeuffer, P. Raith, E.-B. Bröcker, A. Trautmann

http://www.aerzteblatt.de/v4/archiv/pdf.asp?id=61998