Food allergy occurs when the body recognizes protein in certain food as foreign. When this happens, the body overreacts and causes symptoms and this can occur with even small amounts of food protein. Food allergy can occur in both children and adults. Worry and concern over food allergy often causes people to limit their diet in very restrictive ways. Sometimes these restrictions are not completely necessary.
The following foods are responsible for the vast majority of food allergy.
It is very common for people to feel as if food ingestion causes symptoms. In some people, these are food allergies, in others, food intolerances/sensitivities. It is important to understand and distinguish them because allergic food allergies can be dangerous and life-threatening.
Food allergies can take many forms. These can include anaphylaxis, oral allergy syndrome, food protein enterocolitis, and eosinophilic esophagitis
Symptoms of anaphylaxis related to food ingestion can include hives, swelling, difficulty breathing, difficulty swallowing, flushing, itching, nausea, vomiting, diarrhea, dizziness, low blood pressure, uterine or abdominal cramps and if left untreated, death. These symptoms are caused by an immune system that over-reacts to food proteins. Why food allergy happens in an individual is unknown. It is important to identify the trigger for a person so that proper avoidance can be initiated as well as an action plan for treatment of accidental exposures. Panels of food allergy testing may not be appropriate and an allergist/immunologist can help direct testing and treatment.
Oral Allergy Syndrome
Individuals with oral allergy syndrome will describe symptoms in the mouth and throat of itching and tingling, and rarely swelling, related to the ingestion of certain raw fruits, vegetables and nuts. This kind of food allergy is not systemic in nature and is related to a cross sensitivity between pollen allergy and food. Essentially, the persons immune system confuses food for pollen. This is often benign and self- limited. Most patients can eat these very same foods cooked. Often, however, mouth itching is the first symptom of a more severe food allergy. Therefore, evaluation by an allergist/immunologist if symptoms related to food ingestion are occurring is the best possible first step to diagnosis and treatment.
Food Protein-Induced Enterocolitis Syndrome (FPIES)
FPIES is a delayed food allergy whereby food ingestion causes vomiting, diarrhea, lethargy in severe cases, dehydration and low blood pressure. Like other food allergies, FPIES is triggered by the ingestion of certain food proteins. The most common food triggers include milk, soy and grains. This is typically a disorder of infants and toddlers but is rarely seen in adults.
Eosinophilic Esophagitis (EoE)
EoE is a gastrointestinal disorder where allergy cells, called eosinophils, collect in the esophagus. These cells cause inflammation, swelling in the esophagus and can lead to symptoms of difficulty swallowing food, food impaction, and abdominal pain. Most literature supports the presence of underlying food allergy as a cause for EoE. Many people with EoE also experience other allergic disorders like nasal allergy and asthma.
The diagnosis of food allergy requires careful consideration of an individual’s history, symptoms, and thorough knowledge of food allergy principles. Often allergists/immunologists will use skin testing and/or blood testing to diagnose and make decisions about food avoidance. In addition, supervised, oral food challenges may be utilized.
Treatment of food allergies involves not just identification about the triggers, but steps to avoid the allergen trigger as well as education about treatment. An epinephrine autoinjector is prescribed for only certain kinds of food allergy. Some food allergies require strict food avoidance while some food intolerances may allow small amounts to be ingested safely.
An allergist/immunologist is able to provide you with advice and can help you properly diagnose and manage your condition.