Food Allergy

What is food allergy?

A food allergy is an abnormal response of the body to a certain food. It is important to know that this is different than a food intolerance, which does not affect the immune system, although some of the same symptoms may be present.

Prevention & Risk Treatment

Prevention & Risk Treatment

What causes food allergy?

Before having a food allergy reaction, a sensitive child must have been exposed to the food at least once before, or could also be sensitized through breast milk. It is the second time your child eats the food that the allergic symptoms happen. At that time, when IgE antibodies react with the food, histamines are released, which can cause your child to experience hives, asthma, itching in the mouth, trouble breathing, stomach pains, vomiting, and/or diarrhea.

What is the difference between food allergy and food intolerance?

Food allergy causes an immune system response, causing symptoms in your child that range from uncomfortable to life-threatening. Food intolerance does not affect the immune system, although some symptoms may be the same as in food allergy.

What foods most often cause food allergy?

Approximately 90 percent of all food allergies are caused by the following eight foods:

  • Milk
  • Eggs
  • Wheat
  • Soy
  • Tree nuts
  • Peanuts
  • Fish
  • Shellfish

Eggs, milk, and peanuts are the most common causes of food allergies in children, with wheat, soy, and tree nuts also included. Peanuts, tree nuts, fish, and shellfish commonly cause the most severe reactions. Nearly 5 percent of children under the age of five years have food allergies. From 1997 to 2007, the prevalence of reported food allergy increased 18 percent among children under age 18 years. Although most children "outgrow" their allergies, allergy to peanuts, tree nuts, fish, and shellfish may be lifelong.

What are the symptoms of food allergy?

Allergic symptoms may begin within minutes to an hour after ingesting the food. The following are the most common symptoms of food allergy. However, each child may experience symptoms differently. Symptoms may include:

  • Vomiting
  • Diarrhea
  • Cramps
  • Hives
  • Swelling
  • Eczema
  • Itching or swelling of the lips, tongue, or mouth
  • Itching or tightness in the throat
  • Difficulty breathing
  • Wheezing
  • Lowered blood pressure

According to the National Institute of Allergy and Infectious Disease, it does not take much of the food to cause a severe reaction in highly allergic people. In fact, as little as 1/44,000 of a peanut kernel can cause an allergic reaction for severely allergic individuals.

The symptoms of food allergy may resemble other problems or medical conditions. Always consult your child's doctor for a diagnosis.

Children's Team

Children's Team

Providers

Departments

Departments

Food Allergy Program

Correctly identifying a food allergy can be difficult. So, it’s important that your child sees pediatric specialists with particular expertise in food allergy.

Gastroenterology, Hepatology and Nutrition

Our gastroenterology experts provide expert diagnosis and treatments for children with digestive, liver, and nutrition disorders.

Allergy and Immunology

At Children’s National, children affected by allergies and complex immunologic disorders benefit from our specialists’ expertise, because our doctors treat children and only children with these conditions.

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