The 6 Food Allergens Parents Should Know

Allergic Reactions

Feb 7, 2018


Food allergies affect 1 in 13 children, or approximately two kids in every classroom. Despite the high prevalence of food allergies, many people don’t understand the impact allergies can have on a child’s life. Children may experience bullying, and parents are often hesitant to allow them to participate in some fun activities like eating out or going to sleepovers because they fear an allergic reaction.

Additionally, there is still widespread misinformation about proper testing and treatment for food allergies. As many as 40 percent of children with food allergies have had a severe allergic reaction like anaphylaxis, which can be fatal. While these reactions aren’t entirely avoidable, they can be largely prevented with education on food allergies and diagnosis and treatment from a medical professional.

How Food Allergies Work

A food allergy is the body’s immune system response to a food allergen. The body treats this food allergen as a hostile invader and attacks the substance with immunoglobulin E (IgE) antibodies. One byproduct of this interaction is a chemical called histamine, which causes the swelling and inflammation associated with allergies.

Common Food Allergies in Children

While your child could be allergic to any food, 90 percent of food allergies in children are caused by the following six foods:

  • Milk – This allergy is the most common for infants and toddlers and usually appears shortly after starting milk-based formula. An allergic child may experience eczema, vomiting, gassiness, colic or hives. These reactions can also occur after breastfeeding if the mother’s diet includes dairy. A breastfeeding mother can eliminate dairy from her diet or infants can be fed with soy-based formula or extensively hydrolyzed formula to reduce the chance of a reaction. This allergy is not the same as lactose intolerance, which is an inability to digest milk.
  • Eggs – Fortunately, egg allergies rarely cause anaphylaxis, and like milk allergies, many kids outgrow them. Egg allergies are usually caused by ingesting egg whites, but children should also avoid egg yolks because of the high rate of cross-contamination. Be aware that many vaccines, like the flu vaccine, contain egg ingredients. While they are safe for most kids with egg allergies, children with severe allergies may want to receive the vaccine at their pediatrician’s or allergist’s office where they can access emergency allergy care.
  • Peanuts – Though peanuts are actually legumes, people with a peanut allergy have an increased risk for a tree nut allergy. Peanut allergies usually last for life. Candies, ice creams, thickened sauces and foods in Asian restaurants frequently have peanuts in them, so ensure your child avoids these foods if possible. Packaged snacks also carry a risk of cross contamination, as the same packing equipment may be used on nut-free products and foods with nuts in them.
  • Soy – Like egg allergies, soy allergies rarely cause anaphylaxis. If you notice your baby is not responding well to soy-based baby formula, consider switching to extensively hydrolyzed protein or amino acid elemental formula. Soy oil and soy lecithin may be safe for a child with a soy allergy since very little soy protein is actually contained in these ingredients.
  • Wheat – Children with wheat allergies need to be especially careful, as wheat is the most frequently used grain product in the U.S. Fortunately, there are now many wheat-free pastas, breads and cereals available. This allergy is not the same as gluten sensitivity or celiac disease, which is an immune system response within the digestive tract.
  • Tree nuts – Like peanut allergies, tree nut allergies usually last for life. Tree nuts include any nut with a hard shell, like almonds, cashews, walnuts, pistachios, pecans, hazelnuts, macadamia nuts and Brazil nuts, among others. Children with one tree nut allergy are more likely to have another.

While fish and shellfish are two of the eight most common allergies, they are more prevalent in adults than children.

Testing for Food Allergies

Because there is no cure for food allergies, the best way to prevent a severe allergy attack and anaphylaxis is to avoid all foods which may contain the allergen. An allergist can help determine which specific allergies your child has by conducting tests, and a nutritionist can help you and your child create a safe diet plan that doesn’t deprive them entirely of foods they enjoy.

There are four tests an allergist may administer to confirm a child’s food allergy:

  • Skin prick test – The allergist will put a small liquid sample of each allergen on the skin, then prick the skin with a hair-thin, painless needle. If the body develops a wheal – an itchy bump – this indicates an allergy. There is a high false-positive rate, but a low false-negative rate for this test.
  • Blood test – Your child’s blood will be drawn and tested for the presence of IgE antibodies. Unlike the skin prick test, these results are not immediate and may take a week or two to come back.
  • Oral food challenge – In situations where an allergist is unsure if your child has a food allergy, they may ask them to eat the food under medical supervision in increasingly larger amounts. If your child has a reaction, they have immediate access to allergy care.
  • Trial elimination diet – When multiple foods may be the cause of an allergic reaction, your allergist may have your child simplify their diet for several weeks, then reintroduce potential allergens to their diet one at a time to track any change in symptoms. This is potentially unsafe, so your child should only attempt this diet if it’s supervised by an allergist.

What to Do During an Allergy Attack

Food allergies range in severity and can affect the skin, gastrointestinal tract, respiratory tract or cardiovascular system. Mild skin reactions are the least disruptive, and can typically be handled with over-the-counter antihistamines. More severe reactions may lead to potentially fatal anaphylaxis, characterized by difficulty breathing, drops in blood pressure and dizziness or loss of consciousness.

During anaphylaxis, an epinephrine shot must be administered as quickly as possible. Timing does make a difference, so you shouldn’t wait to see if symptoms worsen before giving the shot. You can also give your child other allergy medications to ease their symptoms, but these should always be in addition to, never a substitute for, epinephrine.

After administering the shot, you will need to call 911 or take your child to the emergency room. Even when initial symptoms of anaphylaxis subside, people can experience a resurgence of allergy symptoms, called a biphasic reaction. They should be monitored for four to eight hours after their initial reaction to make sure their symptoms don’t come back.

Receive Emergency Allergy Care at Complete Care

No matter how stringent your child’s diet is, you can’t always be there to monitor what they eat or stand over the shoulder of every cook in every kitchen. Sometimes the unexpected happens, and your child may need emergency allergy care. At Complete Care, our compassionate doctors, nurses, and specialists prioritize your family’s comfort in this distressing time and provide you with immediate quality care.

Visit us at any of our locations in Texas or call us for more information about the emergency services we provide.