If you don’t feel inclined or able to read a just-released, 576-page report on food allergies, it can be diluted to some quick essentials: The incidence of allergies is still quite rare, and their prevalence, contrary to popular belief, is not necessarily on the rise. No accurate estimate for how many people suffer from allergies is currently available. The tome, just released by the National Academies of Sciences, Engineering, and Medicine, covers all aspects of food allergies, including their incidence, causes, prevention, treatment, and public policies. It makes particular reference to food allergies with regard to pediatrics: Many if not most of people’s food allergies are first diagnosed in childhood.
The study collated and examined the available previous research on food allergies and came away with valuable conclusions and some guidance on educating the public, as well as healthcare providers, moving forward. And the issue is surprisingly complicated.
First, the report suggests that the public doesn’t understand what an allergy is, confusing intolerances with true allergies. A true food allergy causes an immune system response and can have a range of symptoms ranging from “severe” to “fatal.” Anaphylaxis, which can happen in just seconds and is sometimes fatal depending on the severity of the reaction, is not ever present in an intolerance. Though some people may refer to their lactose intolerance or celiac disease as “allergies,” these conditions are “usually limited to gastrointestinal symptoms [and] cannot result in death,” said the study’s editor, Dr. Virginia Stallings, professor of pediatrics at the Perlman School of Medicine and the Children’s Hospital of Philadelphia. Allergies and sensitivities or intolerances, she said, can cause confusion, but “they are distinct” from one another. Food trends, such as an increasing awareness of things like "gluten sensitivities" and "carbs" likely muddy the issue as well.
What constitutes an allergy is further complicated by the fact that there is, to date, no truly reliable test for allergies. Both skin and blood tests, the report says, can be misleading, especially when done in large “panels” covering wide arrays of foods. There are eight food groups that are considered “major allergens”: milk, eggs, peanuts, tree nuts, wheat, soy, fish, and crustacean shellfish. Other foods can be allergens but are usually much less common and much less severe.
Still, tests for the major allergens can be inconclusive. “You can test ‘positive’ for foods that you are perfectly fine to eat,” and even more alarmingly, Dr. Stallings said, tests can be negative for foods that one is “actually allergic to.” Furthermore, she said, “Many babies and small children outgrow their allergies,” so one may be allergic to milk for a year but then no longer. “In that case,” she said, “it’s not useful to eliminate whole groups of foods from a diet” out of a misconceived idea that a child is allergic. “The gold standard,” Dr. Stallings said, “is a challenge test,” performed by a certified, respected allergist. In a challenge test, the suspected allergen is given in small but increasing amounts, under supervision (never at home, doctors warn), and monitored for reactions. This is the best way to check if a child has outgrown a particular allergy.
Though the report does not ultimately rule out the possibility that more people suffer from food allergies today, it does conclude that there is nothing to suggest that this is the case. Atopic dermatitis, or eczema, however, is on the rise, and this can make people more susceptible to various allergens including food, “through the defective and inflamed skin barrier.” This, however, would mean that any allergy produced would be temporary and dependent upon the condition of the skin.
One thing is for certain: Old-school rules about how to introduce new foods to young babies no longer apply and can in fact do more harm than good. Extensive research now exists to show that introducing highly allergic foods such as nuts within the first year of a baby’s life can decrease the chance of an allergy.
The report ultimately aims to achieve some seemingly doable things: the editors hope to educate the populace and to disperse more accurate information, dispelling some of the misinformation that is currently available.
