Food Allergies

Symptoms usually start as soon as a few minutes after eating a food and as long as two hours after. In some cases, after the first symptoms go away, a second wave of symptoms comes back one to four hours later (or sometimes even longer). This second wave is called a biphasic reaction.

Food allergies happen when the immune system – the body's defense against infection – mistakenly treats proteins found in food as a threat. As a result, a number of chemicals are released. It's these chemicals that cause the symptoms of an allergic reaction.

The most common food allergy signs and symptoms include:
  • Tingling or itching in the mouth.
  • Hives, itching or eczema.
  • Swelling of the lips, face, tongue and throat or other parts of the body.
  • Wheezing, nasal congestion or trouble breathing.
  • Abdominal pain, diarrhea, nausea or vomiting.
  • Dizziness, lightheadedness or fainting.
Eight things cause about 90% of food allergy reactions:
  • Milk (mostly in children)
  • Eggs.
  • Peanuts.
  • Tree nuts, like walnuts, almonds, pine nuts, brazil nuts, and pecans.
  • Soy.
  • Wheat.
  • Fish (mostly in adults)
  • Shellfish (mostly in adults)

 

Laura Rogers Allergy & Asthma MD