About Food Allergies
1. What is a food allergy?
- A food allergy is an abnormal response to a food triggered by the body’s immune system.
- A food allergic reaction is a true immune response in which the body identifies certain foods as harmful. The response is an allergic reaction that can range from mild to life threatening.
- Food allergy is the leading cause of anaphylaxis, a severe allergic reaction that is rapid on onset and can be fatal if not treated immediately.
2. What foods can cause an allergic reaction?
Any food can cause an allergic reaction, but there are eight major food allergens in the United States that account for 90% of serious allergic reactions. They include:
In adults, common foods include:
Any food can cause an allergic reaction, but there are eight major food allergens in the United States that account for 90% of serious allergic reactions. They include:
- Tree nuts (walnuts, almonds, pecans, pistachios, cashews)
- Eggs
- Milk
- Peanut
- Shellfish (shrimp, crayfish, lobster and crab)
- Fish
- Soy
- Wheat
In adults, common foods include:
- Shellfish, peanuts, tree nuts, fish and mollusks; and fruits and vegetables
3. Who is at risk for food allergy?
- Typically, one who has a parent or sibling with hay fever, eczema, asthma, or food allergies are at a greater risk for developing a food allergy.
- Two parents who have allergies pose a greater risk for someone who only has one parent with an allergy.
- Children with moderate to severe eczema are at risk for developing food allergy, especially to milk, egg, and peanut.
4. Is there a cure for food allergies?
There is no cure for food allergies. Strict avoidance of the offending food is the only way to prevent a reaction!
There is no cure for food allergies. Strict avoidance of the offending food is the only way to prevent a reaction!
5. Will I outgrow my food allergy?
- Most children will outgrow milk, wheat, egg, and soy by late childhood and sometimes as late as the teenage years. Fewer children outgrow peanut, tree nuts and seafood.
- Current recommendations suggest avoiding allergens over time may promote future tolerance, especially with cow’s milk, egg, and soy. This is found in both adults and children. However, early results from newer experimental data suggest that small exposures to relevant allergens might promote tolerance as well.
- A decrease in IgE antibodies may be associated with outgrowing the allergy.
- Food allergy developed in adulthood tends to be life long.
6. Is food allergy and food intolerance the same?
No. There is a very serious difference between food allergy and food intolerance.
Other intolerances and conditions can be confused with a food allergy. Your healthcare provider can help determine possible causes for your symptoms.
No. There is a very serious difference between food allergy and food intolerance.
- A food allergy involves IgE and histamine. Food intolerance is a non-IgE, non-histamine reaction, e.g. Celiac involves the immune system but is non-IgE; Heiner’s syndrome is non-IgE as well. Dermatitis herpetiformis is a skin rash but a sign of food intolerance. FPIES involves the GI tract and is non-IgE..
- Food intolerance usually involves the GI tract, causing uncomfortable symptoms like abdominal pain, nausea, vomiting and diarrhea, but there is no risk of anaphylaxis, a serious allergic reaction that typically comes on quickly and may cause death.
Other intolerances and conditions can be confused with a food allergy. Your healthcare provider can help determine possible causes for your symptoms.
7. Is gluten intolerance an allergy?
No. Gluten intolerance does not involve IgE antibody and is not considered a food allergy.
No. Gluten intolerance does not involve IgE antibody and is not considered a food allergy.
- Gluten is a part of wheat, barley, and rye.
- Gluten is associated with celiac disease.
- Celiac disease develops when the immune system responds abnormally to gluten.
8. Is it safe to receive the flu shot or routine vaccines for patients with an egg allergy?
Recent studies show that many individuals with egg allergy can tolerate the flu vaccine as well as MMR and VZV. However, people with a history of allergy to egg, with or without a history of anaphylaxis, should talk with their healthcare professional to discuss whether they can safely receive egg-based vaccines.
Recent studies show that many individuals with egg allergy can tolerate the flu vaccine as well as MMR and VZV. However, people with a history of allergy to egg, with or without a history of anaphylaxis, should talk with their healthcare professional to discuss whether they can safely receive egg-based vaccines.
9. What should I do if a food allergy is suspected?
- If a food allergy is suspected, it is recommended to ask your health care professional for any necessary prescribed medications and a referral to a board certified allergist for further evaluation.
- Seeking a diagnosis from an allergist trained in immunology/allergy is important, due to health concerns if a patient is incorrectly diagnosed.
- As soon as you suspect a food allergy may exists, consider keeping a written diary, being sure to include suspect foods, timing, and any type of reactions that occur.
10. What can I expect at my first visit with an allergist?
An evaluation of food allergy begins with a detailed history of the individual, discussing a list of suspect foods, the quantity of food causing the reaction, the time between exposure and reaction, the symptoms presented, if symptoms improved after eliminating the suspect food, and other detailed information. As soon as you suspect a food allergy may exist, consider keeping a written diary, including all the above.
Your doctor may also perform some or all of the following:
If a food allergy diagnosis is made, your allergist will provide you with any necessary medication. Educational materials should also be provided, including an emergency action plan.
References:
http://www.phadia.com/en/Products/Allergy-testing-products/ImmunoCAP-Allergen-Information/Food-of-Plant-Origin/Grains/Gluten-/
http://www.aaaai.org/Aaaai/media/MediaLibrary/PDF%20Documents/Practice%20and%20Parameters/Anaphylaxis-2010.pdf
http://www.aaaai.org/Aaaai/media/MediaLibrary/PDF%20Documents/Practice%20and%20Parameters/food-allergy-2006.pdf
http://www.niaid.nih.gov/topics/foodallergy/clinical/documents/faguidelinesexecsummary.pdf
http://www.niaid.nih.gov/topics/foodallergy/clinical/documents/faguidelinespatient.pdf
An evaluation of food allergy begins with a detailed history of the individual, discussing a list of suspect foods, the quantity of food causing the reaction, the time between exposure and reaction, the symptoms presented, if symptoms improved after eliminating the suspect food, and other detailed information. As soon as you suspect a food allergy may exist, consider keeping a written diary, including all the above.
Your doctor may also perform some or all of the following:
- Discussion of the patient’s history (including food journal)
- A physical examination
- Skin prick tests (useful in screening patients with suspected food allergy)
- Serum tests for food specific IgE antibodies
- Trial elimination diet
- Oral food challenge(s)
- Discussion of other related disorders, i.e., asthma, eczema, and seasonal allergies
If a food allergy diagnosis is made, your allergist will provide you with any necessary medication. Educational materials should also be provided, including an emergency action plan.
References:
http://www.phadia.com/en/Products/Allergy-testing-products/ImmunoCAP-Allergen-Information/Food-of-Plant-Origin/Grains/Gluten-/
http://www.aaaai.org/Aaaai/media/MediaLibrary/PDF%20Documents/Practice%20and%20Parameters/Anaphylaxis-2010.pdf
http://www.aaaai.org/Aaaai/media/MediaLibrary/PDF%20Documents/Practice%20and%20Parameters/food-allergy-2006.pdf
http://www.niaid.nih.gov/topics/foodallergy/clinical/documents/faguidelinesexecsummary.pdf
http://www.niaid.nih.gov/topics/foodallergy/clinical/documents/faguidelinespatient.pdf