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The Alarming Reason Why So Many People Have Food Allergies, Says Yale

Researchers propose three behaviors that may be triggering an unnecessary immune response.

Today, some 32 million Americans have food allergies, a number that's higher than ever before. The CDC reports that 1 in 13 children—or about two students per classroom—has a food allergy. The question is, what's causing this epidemic?

In a paper published today in the journal Cell, four Yale immunobiologists propose that an exaggerated activation of our food quality control system is largely to blame for the heightened prevalence of food allergies. (Related: The 7 Healthiest Foods to Eat Right Now.)

Prior to this research, a prevailing theory suggested an absence of natural pathogens—such as parasites in the modern environment—may be causing our bodies to become hypersensitive to certain foods. After all, our immune system evolved over time to deal with such natural threats, and now that we don't encounter them, it reacts to something we do encounter every day—food.

Now, the immunobiologists say our current food quality control system, which is designed to protect us from eating harmful foods, may be the culprit for why so many Americans are developing allergies to common foods. Between the unnatural substances in heavily processed foods and environmental chemicals in dishwashing detergent, for example—in addition to the absence of natural microbial exposure—all disrupt the food quality control program.

So, how does this affect you or your loved ones? Think about it this way: how are we supposed to treat these allergies without knowledge of why it's happening?

"We can't devise ways to prevent or treat food allergies until we fully understand underlying biology," said co-author Ruslan Medzhitov, Sterling Professor of Immunobiology and investigator for the Howard Hughes Medical Institute in a statement shared with Eat This, Not That! "You can't be a good car mechanic if you don't know how a normal car works."

There's a type of immune system response that fires off when we ingest toxins and works to neutralize the threat. However, this same response also triggers allergies—both environmental and food. Again, this hypersensitivity to pollen and gluten—for example—occurs as a result of the lack of true natural threats (parasites) in today's food system.

According to this original theory, this immune response targets harmless proteins found in certain food groups, such as those found in the big 8 food allergens (milk, eggs, peanuts, tree nuts, fish, shellfish, wheat, and soy).

Yale researchers, however, are now theorizing that three other environmental factors have influenced the natural food quality control system, arguing they have also signficantly contributed to our immune system's hypersensitivity to various foods.

"One factor is increased use of hygiene products and overuse of antibiotics and, secondly, a change in diet and the increased consumption of processed food with reduced exposure to naturally grown food and changed composition of the gut microbiome," Medzhitov said.

"Finally, the introduction of food preservatives and environmental chemicals such as dishwashing detergents introduced novel elements for immune system to monitor."

In short, the authors of this paper propose these behaviors are what's prompting the immune system to attack food proteins in the same way it would to toxic substances. 

Until more research is conducted and we have more clarity around actions we can take day-to-day to lessen our exposure of these unnatural substances and chemicals, in the interim, what better reason to limit your consumption of processed foods even further?

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Cheyenne Buckingham
Cheyenne Buckingham is the former news editor of Eat This, Not That! Read more about Cheyenne
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