According to the Centers for Disease Control and Prevention, the incidence of food allergies increased by 50 percent between 1997 and 2011. It is estimated that 8 million children report having a food allergy, which is about 1 out of every 13 children. Peanuts, tree nuts, milk, eggs, wheat, soy, fish and shellfish are the eight most commonly diagnosed food allergens. However, more than 170 foods have been implicated in food allergies. In an environment in which parents are becoming increasingly aware of food allergies, confusion and misinformation persist, making it difficult to make informed decisions.
Food Allergies, Defined
A food allergy occurs when the body has a recurring immune response to a particular food. This response can range from experiencing mild symptoms to a life-threatening situation.
In those who have a food allergy, the immune system believes that the food’s protein is harmful, and this is what causes a reaction.
On first exposure to a potential allergen, the body will make an antibody called Immunoglobulin E (IgE). The next time the food is ingested, the immune system will activate the antibody to respond. This reaction usually occurs within minutes to a few hours of ingestion, and will occur every time the food is ingested.
Mild and severe symptoms can include the following.
If mild symptoms improve with the use of an antihistamine, then observation at home can continue. However, if symptoms do not improve or epinephrine is used, seek emergency medical treatment. If this is a first-time reaction, being seen in the emergency room may be the best course of action. In addition, for a first-time reaction, a follow-up with your healthcare provider would be recommended to obtain a diagnosis and treatment plan.
Another type of adverse food reaction is food intolerance. Food intolerance is often mistaken for a food allergy, but they are two very different things. Food intolerance is not life-threatening, and usually only involves gastrointestinal symptoms such as gas, bloating, pain, constipation and/or diarrhea. Food intolerance may not occur with every ingestion and may be dependent on the amount of the food ingested.
Examples are lactose and gluten intolerance. For instance, when an individual drinks milk and then develops a stomachache and bloating, this called lactose intolerance, and will never progress to a life-threatening situation. Changes in mood or behavior with ingestion of sugars or dyes are also not a food allergy.
Diagnosis and Treatment
Food allergies are diagnosed with a combination of history and testing. There is no testing for food intolerance. When considering if your child has a food allergy, there should be a history of reactions when eating the food in question. An allergist or an allergy-trained provider can do testing for food allergies. There are two options for testing: a skin prick or an Immunocap blood test. Both tests measure antibodies to the food in question. Testing along with the history can confirm a food allergy, but testing alone does not diagnose a food allergy. A large section on skin testing or a high blood IgE result is suggestive of a reaction occurring, but will not identify the severity of the reaction. It’s highly recommended to only test for the food(s) in question. Screening panels are not recommended, as they tend to provide a lot of false positives. Avoiding foods unnecessarily can lead to malnutrition and poor growth.
Typically, the first question asked after a food allergy diagnosis is, “Will my child outgrow his allergy?” The probability of outgrowing a food allergy is better for milk, egg, wheat and soy, with about 85 percent of children outgrowing these allergies. However, fish, peanuts and tree nuts tend to be lifelong allergies, with only about 20 percent of children outgrowing them. A study published in Annals of Allergy, Asthma and Immunology in July 2013 found that the following factors contributed to outgrowing an allergy: a history of only one food allergy, a mild-to-moderate reaction to an allergen and having eczema as the only symptom. Conversely, children with multiple food allergies and anaphylaxis to their allergen were less likely to outgrow their food allergy.
Currently, there is no cure for food allergies. Therefore, after a diagnosis, strict avoidance of the food is recommended. Your provider will likely prescribe an injectable epinephrine device to carry in case of an emergency. Prescribed as a two-pack, it’s very important to always carry them together and not separate them, as 20 percent of individuals with a food allergy will need both doses.
A second dose of epinephrine can be given ten minutes after the first dose if symptoms do not improve or if they worsen. After epinephrine is used, call 911 for further evaluation.
A food allergy and anaphylaxis emergency care plan will also be given. It is always a good idea to carry this plan along with your epinephrine device, and to wear a medical alert bracelet so others will know your child’s allergies.
There is hope for the treatment of food allergies. It is known that 75 percent of children with a milk and egg allergy can tolerate the food in baked goods, and introduction of baked goods with milk and egg will help accelerate tolerance. Speak to your child’s provider to see if this is an option. With ongoing research, hopefully more treatment options will be available in the future.
Diagnosis of a food allergy will require a change in your family’s lifestyle. However, being prepared for an emergency, reading food labels and providing education to those who care for your child will help provide a safe environment.
A few safety tips to keep in mind: Only soap and water remove an allergen from the hands; hand sanitizer does not remove protein. Anaphylaxis will primarily only occur with ingestion of the food, and touching your allergen typically only causes a skin reaction. Always remember: When in doubt, treat a reaction. Having a food allergy can feel overwhelming at first, but will be manageable with education and the help of your child’s provider.
Jodi Shroba, MSN, CPNP, is a CPNP who works in the Allergy, Asthma and Immunology Clinic at Children’s Mercy Hospital in Kansas City, MO. She also serves as the assistant director of its Food Allergy Center, is actively engaged in food allergy research and often lectures on the topic of food allergies.