For an increasing number of Americans, allergies are becoming an everyday part of life. According to the Center for Disease Control (CDC), food allergy rates among minors (0-17 years old) have been steadily rising since 1997 (1), and nearly 20% of adults self-reported food allergies. Recent studies, however, allege that this rate may be greatly inflated as a result of confusion between food intolerances and actual food allergies.
Though food allergies and food intolerances frequently have similar symptoms, potentially leading to popular conflation of the two, food intolerances refer to a range of related conditions causing reactions of a generally lesser degree than food allergies. Food intolerances can be caused by a variety of underlying conditions including food additive sensitivity, irritable bowel syndrome, or a lack of necessary digestive enzymes. In contrast, food allergies are exclusively the result of an immune system reaction. These reactions often affect multiple organs and can be life-threatening which further differentiates food allergies from food intolerances which are generally limited to the gut and, outside of rare exceptions, are not life-threatening (2). The gastrointestinal symptoms of mild food allergies and food intolerances often overlap, including diarrhea, stomach pain, and nausea (3), but food allergies generally also include a range of skin reactions, including hives, swelling, and itchiness. Serious food allergies may also involve Anaphylaxis, during which the body over produces Immunoglobulin E (IgE), a type of antibody, in response to an allergen, and can cause a multisystem reaction. Symptoms include, but are not limited to, difficulty breathing, hives, and a drop in blood pressure. If not treated immediately, the body may go into Anaphylactic shock, which can be fatal (4).
There is growing evidence that a significant amount of food allergy over-reporting may be linked to a widening divergence between the clinical and common definitions of what constitutes an allergy. According to a recent study by the Journal of the American Medical Association (JAMA) Network, whereas adult self-reporting of food allergies suggests that about 19% of adults possess at least one food allergy, the descriptions given by only 11% of these reports were considered “convincing” by researchers. A description of one’s allergy was considered “convincing” if the symptoms described were consistent with IgE-mediated reactions, including swelling, trouble breathing, chest pain, vomiting or fainting. Lesser symptoms, including itching, stomach pain, and rashes, were not considered sufficient, and a “diagnosis history to specific allergens and food allergy–related health care use” was also used to confirm convincing food allergies (2). Indeed, only 47.5% of those claiming to have a food allergy were formally diagnosed as such by a physician prior to the study, further suggesting potentially high rates of self-misdiagnosis. Regarding misuse of the term allergy, Professor in Allergy Prevention at the Karolinska Institute, Brengt Björkstén, stated “The term used by common people is clearly different from how it is defined by medical people,” possibly including intolerances and sensitivity in colloquial usage (5).
Other sources of such misdiagnosis may also be to blame for this discrepancy. One of the most common methods of child food allergy diagnosis, Food Allergen Panel Testing, has been cited as having an abnormally high false positive rate. One study published in the Journal of Pediatrics found that 88.9% of patients diagnosed with one or more food allergies were able to re-introduce at least one these foods into their diet, if they had been the subject of a false-positive. Indeed, according to Clare Mills, head of the allergy research team at the Institute of Food Research, “The only way you can really objectively diagnose a food allergy is by feeding the person the food, which has a certain hazard” (5).
The growing rate of allergy diagnoses continues to be the source of much debate in the medical community. “We believe that it’s an important health issue,” says Jorgen Schlundt, WHO research director, “We also believe that too little effort has gone into it in the past” (5). Hopefully, increased awareness will encourage people with suspected allergies to get formally diagnosed before announcing they are allergic.
Edited by: Chase Breimeier
Illustrated by: Allen Chen