Each year, millions of Americans have allergic reactions to food, which can be broken down into two categories of food allergies:
- Immunoglobulin E (IgE) mediated. Symptoms result from the body’s immune system making antibodies called Immunoglobulin E (IgE) antibodies. These IgE antibodies react with a certain food.
- Non-IgE-mediated. Other parts of the body’s immune system react to a certain food. This reaction causes symptoms but does not involve an IgE antibody. Someone can have both IgE-mediated and non-IgE-mediated food allergies.
IgE-mediated food allergies
Although most IgE-mediated food allergies cause relatively mild and minor symptoms, some food allergies can cause severe reactions, and may even be life-threatening. This type of severe allergic reaction is called anaphylaxis. The symptoms of anaphylaxis may occur shortly after having contact with an allergen and can worsen quickly. Anaphylaxis must be treated right away to provide the best chance for improvement and prevent serious, potentially life-threatening complications. Symptoms of anaphylaxis usually involve more than one part of the body such as the skin, mouth, eyes, lungs, heart, gut, and brain. Symptoms of anaphylaxis can include:
- Skin rashes and itching and hives
- Swelling of the lips, tongue, or throat
- Shortness of breath, trouble breathing, and/or wheezing (whistling sound during breathing)
- Dizziness and/or fainting
- Stomach pain, vomiting, or diarrhea
- Feeling like something awful is about to happen
Epinephrine is the medicine used to treat anaphylaxis. Epinephrine is safe and comes in an easy-to-use device called an auto-injector. After giving epinephrine, always call 911 or a local ambulance service. Tell them that you or your child is having a serious allergic reaction and may need more epinephrine. Sometimes, a reaction is followed by a second, more severe, reaction known as a biphasic reaction. This second reaction can occur within 4 to 8 hours of the first reaction or even later, which is why people should be watched in the emergency room for several hours after anaphylaxis.
The best way to avoid anaphylaxis is to stay away from potential allergens. The FDA food allergen label law requires foods to state if they contain a top 8 food allergen (milk, egg, peanut, tree nut, wheat, soy, fish, crustacean shellfish). Foods that contain these allergens must say so in plain English, so be sure to read the label every time you buy a product, even if you’ve used it before as ingredients can change. In situations where ingredients are not available, take necessary precautions to avoid cross-contact.
Non-IgE-mediated food allergies
On the other hand, most symptoms of non-IgE-mediated food allergies involve the digestive tract. Symptoms may be vomiting and diarrhea and can take longer to develop and may last longer than IgE-mediated allergy symptoms. Sometimes, a reaction to a food allergen occurs up to 3 days after eating the food allergen. When an allergic reaction occurs with this type of allergy, epinephrine is usually not needed. In general, the best way to treat these allergies is to stay away from the food that causes the reaction. Below are examples of conditions related to non-IgE-mediated food allergies:
- Eosinophilic esophagitis (EoE) is an inflamed esophagus. With EoE, swallowing food can be hard and painful. EoE is treated by special diets that remove the foods that are causing the condition. Medication may also be used to reduce inflammation.
- Food protein-induced enterocolitis syndrome (FPIES) is another type of food allergy. It most often affects young infants. Symptoms usually don’t appear for two or more hours. Symptoms include vomiting, which starts about 2 hours or later after eating the food causing the condition. The foods most likely to cause a reaction are dairy, soy, rice, oat, barley, green beans, peas, sweet potatoes, squash, and poultry.
- Allergic proctocolitis is an allergy to formula or breast milk. This condition inflames the lower part of the intestine. It affects infants in their first year of life and usually ends by age 1 year. When properly diagnosed, symptoms resolve once the offending food(s) are removed from the diet.
Share your experiences and help make a difference
As the oldest and largest nonprofit patient organization dedicated to improving the quality of life for people with asthma, allergies, and related conditions, the Asthma and Allergy Foundation of America (AAFA) has been serving the community for over 60 years through education, advocacy, and research. To help drive the future of food allergy research, Kids With Food Allergies, a division of AAFA, created the first and only patient-centered Food Allergy Patient & Family Registry (Registry). The Registry is a secure, private, Web-based program where participants will be able to share information about their experiences and opinions about living with food allergies. With 5% of children and 4% of adults in the United States with food allergy, the goal of the Registry is to collect “real-world evidence” to support research that will improve quality of life and, ultimately, help to end food allergy.
Food allergies are a growing food safety and public health concern, and more precise data are required to unravel all of the scientific and quality-of-life issues surrounding food allergies. In addition to the physical and emotional toll food allergy has on those affected, the economic burden of food allergies on families is high as well. Costs include not only out-of-pocket expenditures for medical services, but also the costs of allergen-free foods and special childcare arrangements. Because of this, patient participation in medical research is critical and helps researchers understand the issues involved with living with the disease—giving them unique insight that doctors and other health care providers may not be able to give.
While food allergy may feel all-encompassing at times, it’s important to remember that you have the power to take control of your surroundings to help mitigate potential reactions. If you or someone you know suffers from food allergy, we invite you to participate in our Food Allergy Patient & Family Registry so you can help inform food allergy research. By sharing you or your family’s experiences, researchers can collect, manage, and analyze data from and about people with food allergies to advance research through patient information. To get started, simply register online, enter basic information, and complete a confidential Food Allergy History & Diagnosis survey. For more information on food allergy signs, treatment, and management, visit www.aafa.org and www.kidswithfoodallergies.org.