Today, it seems as if every classroom has a little Henry or Jennifer who can't eat peanuts or wheat. So if you are caring for young children, chances are that you are familiar with food allergy, a potentially life-threatening condition that can cause many families severe distress.
According to the American Academy of Allergy, Asthma and Immunology, about 8 percent of children have food allergies, compared to 2 percent of adults. The good news those figures reflect is that some, though not all, food allergies can be outgrown over time, particularly when they stop eating the food.
Below, Jacqueline Pongracic, MD, division head of allergy, at Children's Memorial Hospital in Chicago, discusses how to recognize the signs of a food allergy, as well as how to ensure proper diagnosis and follow-up, so you can keep your child safe.
What is a food allergy?
It's a food reaction that happens through the immune system. That's important to understand because other types of food reactions exist, such as intolerances. An example of that would be lactose intolerance, which doesn't occur through the immune system but because of a lack of an enzyme in the gut that breaks down lactose.
What is happening in the body when one has a food allergy?
When someone has an allergy the immune system produces an allergy antibody that we call IgE, in response to a particular protein. Once IgE is produced, it circulates in the body until it encounters allergy cells. When the IgE encounters those cells, it attaches to them. Then the antibody waits like a guard watching for that particular protein.
Let's say an individual produces IgE antibody to egg. When that sensitive individual eats egg again, the egg protein will be absorbed and when it encounters the IgE specific for egg protein, the two join together. When that happens, the allergy cells release a variety of chemicals that can cause the signs and symptoms of an allergic reaction.