Parents of kids with food allergies tend to believe that they, too, have allergies. And in most cases, they're wrong—only 28% of them are actually allergic to the food in question, says a new study published in the Annals of Allergy, Asthma and Immunology.
If a parent has an allergy, then their child is likely to have it too. The problem with these parents is that they think the reverse is also true—if their child is allergic to a particular food, then they, the parent, must also be allergic. But it doesn't work like that.
"Of the 2,477 parents, only 28% of those who self-reported a food allergy actually tested positive," said lead author Melanie Makhija, doctor at the Feinberg School of Medicine, Chicago, in a statement. "This tells us that either people haven’t been tested and are assuming an allergy from a previous reaction to a food, or they haven’t been tested properly and may not truly have an allergy."
Ironically, of the parents in the test who reported no food allergies, 14% tested positive to peanut and sesame allergies.
It comes down to testing. Many of these parents had not been tested for the particular food allergy—they just assumed they had it because their kids did. Others had been tested, but the results only showed low positive results which, says allergist and co-author Rachel Robison, "are more likely to be false positives."
Skin prick tests and even allergy blood tests are not completely accurate. Skin prick tests, for instance, reveal a sensitization to an allergen, but that doesn't mean you actually have an allergy. To know for sure that you have an allergy, you need to eat the food and see what happens. In this test, positive symptoms included hives or angioedema, difficulty breathing, shortness of breath, repetitive coughing, wheezing, or chest tightness, throat tightness, choking or difficulty swallowing, tongue swelling, fainting, dizziness, light-headedness, or decreased level of consciousness, or vomiting. That's quite a list. If none of those occur, you probably don't have an allergy.
In another twist, the fathers of allergic kids showed much higher rates of allergy than the mothers, even though mothers self-reported allergies at a higher rate (13.3% compared with 8.9% of fathers). Fathers, says the study, "had more sensitization to environmental allergens and more food sensitization to peanut, walnut, shellﬁsh, wheat, soy, and sesame." But, even that might not be significant, because mothers with a tendency towards allergies may be more likely to enroll their children in such a study, says the report.
We also know, from a previous study, that most kids who report food allergies in school don't have them, and this, too, is down to parental ignorance. In the Swedish study, it was found that many kids reported a food allergy at school, even though they had lost all sensitivity to that food years before. The reason they were still telling teachers that they couldn't eat certain foods? Their overcautious parents were still forcing them to avoid those foods, even though not eating them was sometimes negatively affecting their growth.
Being careful about allergies is clearly important, because failure to do so can be so disastrous. But being mis-informed doesn't help anyone, and in the case of parents over-protecting their kids, this too can cause long-term harm.