A food allergy is a condition in which certain foods trigger an abnormal immune response .it caused by your immune system recognizing some of the proteins in a food as harmful. Your body then launches a range of protective measures, including releasing chemicals like histamine, which causes inflammation. For people who have a food allergy, even exposure to very small amounts of the problem food can cause an allergic reaction.
How Food Allergies Work
Food allergies involve two parts of your immune system. One is immunoglobulin E (IgE) a type of protein called an antibody that moves through the blood. The other is mast cells, which you have in all body tissues but especially in the digestive tract.
The first time you eat a food you’re allergic to, certain cells make a lot of IgE for the part of the food that triggers your allergy, called an allergen. The IgE gets released and attaches to the surface of mast cells. You won’t have a reaction yet, but now you’re set up for one.
The next time you eat that food, the allergen interacts with that IgE and triggers the mast cells to release chemicals such as histamine. Depending on the tissue they’re in, these chemicals will cause various symptoms. And since some food allergens aren’t broken down by the heat of cooking or by stomach acids or enzymes that digest food, they can cross into your bloodstream. From there, they can travel and cause allergic reactions throughout your body.
You may feel itching in your mouth. Then you may have symptoms such as vomiting, diarrhea, or belly pain. Food allergens in your blood can cause a drop in blood pressure. As they reach your skin, they can trigger hives or eczema. In the lungs, they may cause wheezing. All of this takes place within a few minutes to an hour.
The most common allergenic foods, which account for about 90 percent of all food allergies, are:
- nuts from trees (including hazelnuts, walnuts, almonds, and Brazil nuts)
- peanuts (groundnuts)
- shellfish (including shrimps, mussels, and crab)
Some of the symptoms can include:
Skin rash, itching, hives
Swelling of the lips, tongue
Shortness of breath, trouble breathing, wheezing
Stomach pain, vomiting, diarrhea
Date: June 25, 2019