Food Allergy Symptoms
Lacey was a 35-year old singer, whose asthma was affecting her ability to sing at her best. She told me that her nasal symptoms and asthma got worse in the spring and fall when the pollen counts were the highest. But that didn’t’ explain why she had asthma during the winter, when pollen is not in the air. I took a blood sample to do allergy blood testing for indoor allergies like mold and dust mites. I also suggested testing for food allergies, because she mentioned that she occasionally developed hives.
Her test results showed that she was allergic to trees, grass and ragweed pollen. No surprise. But she was also allergic to tomatoes, wheat and peanuts! She laughed when I told her the results, and said, “I eat peanut butter and jelly sandwiches every day for lunch.” She vowed off the sandwiches, and when she came back a month later, Lacey was grinning. She told me that she was so much better that she didn’t even need her asthma inhalers.
How we diagnose an allergy
- Take a detailed history: Look for genetic and lifestyle risk factors for food allergies. Your history takes into account foods you are eating—because that’s where the culprit is likely to be. For example, in the United States, wheat allergy is much more common than in China, because we eat so much pizza, pasta and bread. In China, the number one food allergy is, you guessed it, rice.
- Rule out sensitivity to food: This is different than a true allergy and often confused. There are various common food sensitivities including lactose intolerance, gluten sensitivity (in severe cases, it’s called Celiac disease) and gastrointestinal reflux (GERD). The symptoms tend to be different and can include digestive problems like gas and pain, nausea, as well as itching, or even joint pain, headaches, rashes and anemia.
- Testing for food allergies: This can be done in two ways. One of the older ways is called skin-prick testing. This is where a drop of a liquid allergen is placed on the surface of the skin and gently pricked with a plastic tooth-pick device. If your skin develops an itchy, red wheal (bump), then this could mean you’re allergic to the particular allergen. This does come with a small risk of having a severe reaction to the allergen.
New advances in testing
The innovative way to test for food allergies is through blood testing. The most precise tests available, called ImmunoCAP and ISAC by Phadia, measure the specific allergen components. The blood is drawn and sent to a lab to be analyzed for levels of individual protein components of the allergen. This is important because being allergic to some protein components is more dangerous than others.
The advantages of blood tests are that they are accurate and safe. You’re not exposed to the allergen, so there’s no risk of having a severe reaction to the test. The ISAC test in particular does precise component testing of specific food and environmental allergens. This gives the advantage of avoiding false cross-reacting positive test, and gives a quantified level of specific allergen.
Contact us today to find out more and get tested.