Food allergy is when your immune system mistakenly treats something in a particular food (most often, the protein) as if it’s dangerous to you. Your body reacts to the food by having an allergic reaction.
Under the umbrella of food allergy there are two classes – IgE-mediated and non-IgE-mediated – which differ by symptoms and when reactions occur. Both classes, however, can involve gastrointestinal symptoms.
Many are familiar with IgE-mediated food allergy, in which symptoms result from the immune system making IgE antibodies when a specific food is eaten. Symptoms generally include two or more body systems: skin, respiratory, gastrointestinal, and cardiovascular. Reactions usually happen quickly, and can be anaphylactic, which is potentially life-threatening.
In contrast, non-IgE-mediated food allergy is less recognized, and involves components of the immune system other than IgE antibodies. It commonly presents with gastrointestinal symptoms, the reactions are often delayed after a food is eaten, and they do not lead to anaphylaxis.
It helps to be aware of the more common non-IgE-mediated food allergy conditions which can affect both adults and children. They may be responsible for symptoms experienced by you or someone you know.
Examples of non-IgE-mediated conditions:
Eosinophilic Esophagitis (EoE) affects the gastrointestinal tract and specifically, the esophagus which is the tube that carries food from the mouth to the stomach. With EoE, large numbers of eosinophils (white blood cells) collect in the esophagus. The foods most commonly associated with EoE are milk, wheat, egg and soy, although it can be associated with environmental allergens like pollen. While difficulty swallowing when eating is a classic symptom, abdominal pain and vomiting can also occur, among other symptoms.
- Learn more at foodallergycanada.ca/EoE
- Watch a free recorded webinar – EoE in adults and EoE in children
- Download a patient sheet in English and French
Food Protein-Induced Enterocolitis Syndrome (FPIES) affects the gastrointestinal tract and typically presents in infancy or early childhood, but can also occur in adulthood. The most common triggers are milk and soy in children, and crustaceans like lobster or shrimp in adults. Symptoms can include severe vomiting, diarrhea and abdominal pain, which usually take place 2-3 hours after eating a food.
- Learn more at foodallergycanada.ca/FPIES
While non-IgE-mediated food allergy does not cause anaphylaxis, it can impact quality of life for the person with this condition and their families. Greater awareness will help support the diagnosis, management and support of those living with conditions like EoE and FPIES.
Learn more about EoE and FPIES at foodallergycanada.ca.
