Diagnosing Food Allergies: Top 4 Recommended Techniques
Diagnosing food allergies can be a tricky thing to do! When your immune system overreacts to a special protein found in a food, you have a food allergy. Sometimes symptoms occur simply by touching, breathing or eating a tiny amount of the food.
My previous post discussed how the immune system makes immunoglobulins as a response to reacting with an allergen, thus this reaction is at the heart of diagnosing food allergies.
True food allergies are reactions that always generate symptoms, usually within minutes to hours. Although any food may cause an allergy, over 90% of significant food allergies are caused by cow’s milk, egg, wheat, soy, peanut, tree nut, fish, shellfish.
People who think they are allergic to a particular food frequently just developed an intolerance. Symptoms of food intolerance and food allergy are similar but differences between the two are important to know because food allergy reactions can be life-threatening.
Although allergic reactions can happen a few hours after eating a trigger food, they usually occur within minutes. The most common food allergy symptoms include:
- Hives or itchy, red skin
- Itchy or stuffy nose, itchy, teary eyes, or sneezing
- Angioedema or swelling
- Vomiting, stomach cramps or diarrhea
Food allergies may cause a severe reaction called anaphylaxis, whose signs include:
- Tingling in the hands, feet, lips or scalp
- Wheezing, tightness in the chest or trouble breathing
- Throat tightness, a lump in the throat, or hoarseness
If you experience any of these symptoms, you should immediately call 9-1-1 emergency!
Many physicians believe if food is eaten and no obvious reaction occurs in a short period of time, then an allergy does not exist. As a Pediatric Ear, Nose and Throat (ENT) physician who sees patients on a daily basis with chronic nasal and sinus symptoms, I do not agree with this belief.
Many of my young patients with food allergy symptoms do not show a sudden flare-up of symptoms, but they simply make more swelling and mucus. Obvious nasal drainage does not occur; therefore, it can be difficult to see that more has slowly been made.
I agree that these food allergies do not cause the alarming allergic reactions classically associated with major allergies. However, I stand by the fact that these reactions count as real allergies.
My patients also suffer from chronic eczema, an extremely common skin rash. Although the exact cause of eczema is not known, a variety of foods can trigger a flare. When patients show eczema rashes in several stages of new itchy areas and old discolored, scaly areas, it becomes difficult to see new flare-ups shortly after eating an offending food.
Many unproven, non-standardized tests exist as methods to reportedly diagnose food allergies. Generally, physicians do not recommend these tests, which are expensive because they are frequently not covered by insurance. A list of non-recommended food allergy tests can be found here.
Recommended methods for diagnosing food allergies include a combination of the things listed below:
1. Allergy assessments begin by taking a detailed history.
2. Blood testing
3. Skin prick testing
4. Food challenge test
The first step to managing a food allergy is getting a correct diagnosis. Self-diagnosis can lead to unnecessary dietary restrictions and inadequate nutrition, especially in children. When diagnosed with a particular food allergy, part of the treatment plan is strict avoidance of that food. On the other hand, an intolerance may allow the patient to eat small quantities of food without having a reaction.
No cure exists for food allergies, and no medications prevent reactions. Education and close monitoring and management by a physician stand as the best options.
*These are opinions of Dr. Momma. Discuss your specific treatments with your physician*