I have asthma and allergies to certain types of chocolate that trigger skin asthma. My mom’s side of the family are allergic to various types of seafood. I had a pretty rough childhood when it came to diet and nutrition due to these restrictions.
Today, my asthma is dormant. Thankfully, it hasn’t been triggered since high school and I can eat chocolate and seafood in moderation. But for many kids born at the turn of the century, the allergy situation has gotten worse. And researchers try to figure out why. But first, let’s break the down the mechanisms behind allergies.
A food allergy results from a chain of biochemical misunderstandings. The first time the immune system encounters an allergen (as a protein that triggers an allergy is known), it mistakes the substance for a hostile invader—perhaps a parasite with a similar molecular profile.
In response, it produces an antibody called immunoglobin E (IgE), which is designed to bind to a specific protein and flag it for attack. These antibodies circulate through the bloodstream and attach to immune-system foot soldiers known as mast cells and basophils, which congregate in the nose, throat, lungs, skin, and gastrointestinal tract.
The next time the person is exposed to the allergen, the IgE antibodies signal the warrior cells to blast the intruder with histamines and other chemical weapons. Tissues in the affected areas swell and leak fluid; blood pressure may fall. Depending on the strength of the reaction, collateral damage to the patient can range from unpleasant—itching, runny nose, nausea—to catastrophic.
As many people with allergies will know and as you might have inferred, these are usually hereditary. They are passed down to your children and their children. There are cases when they don’t manifest in certain members of the family or aren’t as severe as others. We don’t know why. But for the most part, the gist of why food allergies are increasing comes down to exposure.
So if we assume that everybody is born with the same immune system and that some have a slight vulnerability to allergies, we can say that these allergies develop as children grow and interact with their surrounding environment.
Given the mechanism of how our immune system fights allergens, the less it is exposed to these at an earlier stage, the less it will be able to develop familiarity or defense mechanisms for them. Perhaps, apart from less exposure to the elements, our comfortable lives have caused our bodies’ defensive capabilities to atrophy, in a sense.
Though this may be a possible reason for the surge in food allergies, it’s not the only one.
So which culprit is most responsible for the food allergy upsurge? “The illnesses that we’re measuring are complex,” says Sicherer. “There are multiple genetic inputs, which interact with one another, and there are multiple environmental inputs, which interact with each other and with the genes. There’s not one single thing that’s causing this. It’s a conglomeration.”
(Image credit: Hannah Morgan/Unsplash)