A food allergy occurs when our immune system overreacts to a certain protein in a specific food and treats it like an invader. In response, our bodies create allergy antibodies to help attack the invader protein, which causes us to have an allergic reaction. While the what of food allergies is fairly straightforward, why we get them is a multifaceted mystery. In this video, Dr. Katie Marks-Cogan shows us how a range of factors—from genetics to how clean we were as kids—all play a role in why some people develop allergies to food in the first place.

Key Takeaways

  • Food allergies happen when our immune system overreacts to a protein in a certain food and creates allergy antibodies to attack the protein, which causes the symptoms of an allergic reaction.
  • Allergies are caused by a number of things, including genetics and the types of allergens you came in contact with at a young age.
  • One hypothesis is that cleanliness in modern society prevents us from being exposed to the right kind of germs as children, which can lead to more allergies.

Video Transcript

The job of our immune system is to defend our bodies from foreign invaders like bacteria and viruses. A food allergy occurs when our immune system overreacts to a protein in a specific food and treats it like an invader. We then create allergy antibodies to help ourselves attack the protein, which causes us to have an allergic reaction. This might include symptoms like swelling, difficulty breathing, nausea, or vomiting. Food allergies are not caused by one thing. They're multifactorial, meaning they're caused by a number of things. Genetics play a role, as do environmental exposures early in life, things like what your gut was exposed to, or what allergens you came in contact with. There's also a scientific idea called the hygiene hypothesis, which is the idea that cleanliness in modern society has changed. So we often aren't exposed to the right kind of germs as children, and we may develop allergies as a result. Fighting germs helps develop our immune system, so without practice differentiating between harmless and dangerous germs, our immune system might become allergic to something that isn't harmful at all. Another possible factor is vitamin D deficiency, since vitamin D helps the immune system do its job well. Without enough vitamin D, the immune system can make more mistakes than normal, possibly leading to higher numbers of allergies. However, more research is needed on this topic, as too much vitamin D may be harmful as well.