By Genevieve Comar

Take a look at the menu outside the Dining Hall. What do you see? A carefully color-coded, curated page listing hot lunch and a multitude of alternative options. It can be extremely difficult to understand, especially during the quick five second glance you take before you pick out your food from the counter. Now don’t get me wrong; as a person with food sensitivities, I am very grateful that HB provides so many options, however I can’t help but wonder. Why do we need this? Why does our school, and really the entire country have so many allergies? On my cross country team, the entire group of juniors were gluten free and two (including myself) could not have eggs or dairy as well. When talking to my parents and grandparents about it, they always say that there was almost never anyone in their schools who had food allergies, besides the odd peanut or shellfish person. And certainly not to the degree we see today.

There seem to be three prevailing theories. The most common, but not necessarily the most accurate, is the hygiene hypothesis. This was proposed in the 1980s, when German scientists noticed that families with more children tended to have less allergies, while smaller families were more likely to have children with allergies. They hypothesized that this was because in larger families, children are exposed to more sickness and allergens and titled it the Hygiene Hypothesis, which led people to believe that less personal hygiene was necessary to prevent allergies. 

Another theory is the Dual Allergen Exposure Hypothesis, which offers an explanation as to why people with eczema are at a higher risk of developing allergies. It theorizes if a person is exposed to allergens and food protein through the skin (due to the damaged skin barrier of people with eczema) rather than through the digestive system, the body is more likely to see that food protein as an invader. Depending on the severity of the exposure through the skin, this can potentially trigger anaphylaxis and inflammation.

Others point to the food introduction guidelines set by the American Academy of Pediatrics in 2000. Based on the research of the time, they believed it would be best to delay the introduction of peanuts and other potential allergy foods until infants were three years old. Over the next thirteen years, as parents continued to avoid giving their children peanut butter, the number of peanut allergies increased dramatically. It is now estimated that 2% of children are affected by a peanut allergy. New guidelines were set out in 2017, saying instead to introduce peanuts by six months of age, especially for high risk children with eczema or a family history. This nearly twenty year period in which parents avoided peanuts could explain the rapid rise of allergies that we now see today. 

It is likely all three of these hypotheses factor into the modern prevalence of food allergies. As more research comes out, the exact causes of them will be uncovered. This will hopefully lead to more guidelines on the prevention of food allergies at a younger age and ways to facilitate exposure. But for now, the 30 million Americans who have an allergy will continue to live with it.

Sources and Further Reading:

Cleaning up the hygiene hypothesis | PNAS