WHAT IS FOOD ALLERGY?
Food allergy occurs when your immune system overreacts to proteins found in food. This creates “IgE” (allergic antibodies) which reacts with allergic cells to release chemicals like histamine. Symptoms can occur with only a tiny amount of food.
Food intolerance is ANY reaction to food, like lactose intolerance. No allergic antibody is involved. About 25% of the population has a food intolerance, while only a few percent have a true food allergy.
These 8 foods cause 95% of food allergies:
- milk
- egg
- wheat
- soy
- peanut
- tree nut
- fish
- shellfish
A less frequent but treatable food allergy is called “oral allergy syndrome” or “pollen food syndrome.” People who initially have pollen allergy later develop oral symptoms like tingling and itching of their mouth, tongue, lips, and throat. The allergic proteins in the pollens are “shared” between the pollen and food. Allergy shots to pollens usually resolve this allergy.
WHAT ARE SYMPTOMS OF FOOD ALLERGY?
Symptoms generally start within 2 hours of ingestion:
- hives, swelling, flushing, or itchy rash
- throat fullness, itching or swelling of tongue, lips, or throat
- itchy, red, or watery eyes, swollen eyelids
- coughing, wheezing, difficulty breathing
- GI tract: nausea, vomiting, diarrhea, cramps
CALL 911 IMMEDIATELY IF ANY SEVERE SYMPTOMS OCCUR
HOW IS FOOD ALLERGY DIAGNOSED?
After a history and physical exam, we will usually skin test to suspected foods. Occasionally, we perform a “ food challenge” where we introduce gradually increasing amounts of the suspected food under physician supervision.
HOW IS FOOD ALLERGY TREATED?
Completely avoid all allergic foods. Most food allergies are outgrown except for fish, shellfish, peanuts and tree nuts. Read labels for hidden foods. Ask about ingredients on restaurant menu items. We will reevaluate every few years for food allergies which are usually outgrown.
Antihistamines can control mild symptoms. We will prescribe an epinephrine kit for lifethreatening reactions. For patient support, contact Food Allergy Research & Education (FARE). https://www.foodallergy.org