Allergies are a condition that occurs when the body’s immune system sees a substance such as a particular food as a harmful “invader” and overreacts to it. The substances that cause allergic reactions are called allergens, which are what trigger an immune response, also called an allergic reaction.
Food allergies occur most often in babies and children, but a person can develop a food allergy later in life. People can even develop food allergies to foods they have eaten for years with no problems.
What Are Symptoms of a Food Allergy?
Symptoms of a food allergy usually occur within minutes of eating a particular trigger food, and may include:
- Hives or red, itchy skin
- Stuffy or itchy nose
- Sneezing
- Itchy, watery eyes
- Stomach cramps
- Vomiting
- Diarrhea
- Angioedema or swelling
- Anaphylaxis
- Anaphylaxis, a severe allergic reaction, is a medical emergency. If you experience any of the following symptoms call 911 and get to a hospital’s emergency department.
- Tightness in the throat or a lump in the throat
- Hoarseness
- Wheezing
- Chest tightness
- Difficulty breathing
- Tingling in the hands, feet, lips, or scalp
What Causes a Food Allergy?
A food allergy is an allergic reaction that happens when the immune system overreacts to a food or a substance in a food, identifying it as a harmful “invader” and triggering a protective response. Any food can cause a food allergy, but there are eight types of food that account for about 90% of all allergic reactions:
- Eggs
- Dairy products made from cow’s milk
- Peanuts
- Tree nuts
- Fish
- Shellfish
- Soy
- Wheat
- Sesame and other seeds
Other common food allergens include:
What Tests Can Diagnose Food Allergies?
A food allergy is diagnosed starting with a medical history and physical exam.
Tests used to diagnose a food allergy may include:
- Skin prick food allergy test
- Blood tests (specific IgE, ImmunoCAP test)
- Physician-supervised oral food challenge tests
What Is the Treatment for a Food Allergy?
- The main treatment for a food allergy is to avoid the food that triggers an allergic reaction.
- For mild allergic reactions, antihistamines may relieve symptoms.
- For those with severe food allergies who may be prone to anaphylaxis (a severe allergic reaction), a doctor will likely prescribe auto-injectable epinephrine (Epi-pen) to carry at all times in the case of an anaphylactic reaction.
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https://www.allergyuk.org/information-and-advice/conditions-and-symptoms/36-types-of-food-allergy
https://www.aaaai.org/conditions-and-treatments/allergies/food-allergies
https://acaai.org/allergies/allergic-conditions/food/