8 Food Allergy Questions Answered

For families with food allergies, Halloween kicks off a season of hyperawareness. There's monitoring trick-or-treat candy, minding the holiday treats and bringing your own dishes to family meals.

The University of Kansas Health System allergist Marissa Love, MD, answers some of the most common questions about food allergies and sensitivities.

1. What are the most common food allergies?

The top 9 allergens are peanut, tree nuts, cow's milk, egg, soy, wheat, fish, shellfish and sesame.

"Sesame is a new one that's been around, more predominant in Europe, but definitely a top allergen now in the US," says Dr. Love.

2. When to introduce potential allergens to kids?

The recommendations for giving potentially highly allergenic foods to kids have changed dramatically. Dr. Love says its generally best to introduce earlier than previously thought, based off studies on the development of peanut allergy.

"If allergic disease runs in the family, it would be ideal to introduce potentially highly allergenic foods once the baby is developmentally appropriate. In highly allergic families, that's around 4-6 months," she says.

It's recommended to introduce highly allergenic foods by 12 months for all babies.

3. How to introduce food allergens?

Eating it is the best way. Start with very small amounts and prepare it in a way that is easy to ingest. Dr. Love recommends checking with your pediatrician to make sure an infant can swallow the type of texture of the food you're introducing.

"I like to take about a teaspoon to 2 teaspoons of peanut butter, warm it up and thin it out, and then I mix it in with a fruit puree that the patient has already tolerated, like applesauce," says Dr. Love.

She recommends doing this first thing in the morning to monitor for any rashes or reactions. Wait 10 minutes and if nothing happens, give them a little more.

"Many times, people will say, well, the child got a rash on their face. Peanut butter itself can be very irritating to the skin, so if your son or daughter has sensitive skin, put Vaseline around the mouth before you introduce a new food, and that way they won't get what we call an irritant dermatitis," says Dr. Love.

4. What does an allergic reaction to food look like?

In some cases, the first reaction may just be a rash, often a rash on the face.

Frequently with a true food allergy, there are additional symptoms, such as widespread hives, lip swelling, tongue swelling, trouble breathing, drooling or vomiting.

5. What if you are concerned about a severe reaction?

If food allergies run in the family and you are very concerned about food introduction, discuss it further with your pediatrician or primary care physician and see if they would benefit from seeing an allergist. Sometimes, in specific cases, the first food introduction may be done in the clinic.

6. Are food allergies more common now?

There is an increasing incidence of food allergies. Additionally, we are better at recognizing and diagnosing food allergies.

"If you talk to perhaps an older generation, they said, 'Well, we just continued eating that food in small amounts.' And so, things are a little bit different today, where patients and families are a little bit more cautious," says Dr. Love.

7. How are food allergies in kids treated?

There are new treatments in the pipeline that help with desensitization or decrease the severity of a reaction.

There's an oral immunotherapy that has been FDA-approved for a few years now to help make the person less reactive to peanut over time. With that, very small amounts of peanut protein are given to them over the course of time.

There's also a newer indication for medicine that's been around for 10 years. It's an injection medicine called omalizumab.

"That's very, very exciting for people with food allergies," says Dr. Love. "Basically, it binds your allergy antibody in the blood and kind of sweeps it out and reduces the amount you have. So again, not necessarily a cure, but makes it such that the person is less likely to have a severe reaction if they accidentally eat that food."

8. Are food sensitivity tests accurate?

Food sensitivity tests have become widely available online and commercialized. These are usually IgG food testing, and Dr. Love says that board-certified allergists do not offer IgG testing. For food reactions that seem to be IgE driven, our allergists typically use skin prick testing and/or IgE blood testing to look for food-specific allergy antibody.

"That being said, I do see quite a few patients with food intolerance or non-IgE mediated food sensitivities, and I help them navigate that," Dr. Love says. "I feel that it's so important to help the patient navigate their diet. I definitely want to make sure they have access to nutritious food that doesn't make them feel terrible all the time."