With a food allergy, the body reacts as though that particular food product is harmful. As a result, the body’s immune system (which fights infection and disease) creates antibodies to fight the food allergen, the substance in the food that triggers the allergy.
The next time a person comes in contact with that food by touching or eating it or inhaling its particles, the body releases chemicals, including one called histamine, to “protect” itself. These chemicals trigger allergic symptoms that can affect the respiratory system, gastrointestinal tract, skin, or cardiovascular system. These symptoms might include a runny nose, an itchy skin rash, a tingling in the tongue, lips, or throat, swelling, abdominal pain, or wheezing.
People often confuse food allergies with food intolerance because of similar symptoms. The symptoms of food intolerance can include burping, indigestion, gas, loose stools, headaches, nervousness, or a feeling of being “flushed.” But food intolerance:
- doesn’t involve the immune system
- can be caused by a person’s inability to digest certain substances, such as lactose
- can be unpleasant, but is rarely dangerous
According to the U.S. Food and Drug Administration (FDA), up to 6% of children in the United States under age 3 have food allergies. They are less common in adults but, overall, food allergies affect nearly 11 million people in the United States.
Common Food Allergens
A child could be allergic to any food, but these eight common allergens account for 90% of all reactions in kids:
- tree nuts (such as walnuts and cashews)
- shellfish (such as shrimp)
In general, most kids with food allergies outgrow them. Of those who are allergic to milk, about 80% will eventually outgrow the allergy. About two-thirds with allergies to eggs and about 80% with a wheat or soy allergy will outgrow those by the time they’re 5 years old.
Other food allergies are harder to outgrow. Only about 20% of people with allergies to peanuts and about 10% of those allergic to tree nuts outgrow the allergies. Fish and shellfish allergies usually develop later in life and are even more rarely outgrown.
If you have questions about food allergies or whether your child should be tested, contact a health professional and schedule an appointment.