Food allergies are due to an immune system reaction that occurs soon after eating a certain food. They affect about 1 in 20 Americans with cases occurring at any age, but most commonly in babies and young children. While any food may cause an allergic reaction, These eight types of food account for about 90 percent of food allergies: egg, fish, milk, peanuts, shellfish, soy, tree nuts and wheat
Symptoms of a food allergy vary significantly from person to person, as does the amount of food needed to trigger an allergic reaction. While most food-related symptoms occur within two hours of ingestion, in some rare cases, the reaction may be delayed by four to six hours or even longer. Common symptoms of a food-related allergic reaction include hives or swollen airways. The most severe allergic reactions may result in anaphylaxis, which can impair breathing, cause a dramatic drop in blood pressure and affect heart rate to a fatal degree.
Some people may experience an itching and/or tingling feeling in their mouths after consuming certain fruits, which is referred to as pollen-food allergy syndrome or oral allergy syndrome. For example, those allergic to birch pollen can have this reaction when eating an apple. In rare cases, pollen-food allergy syndrome can lead to anaphylaxis.
The diagnosis of a food allergy generally requires a thorough medical history including what and how much you ate, how long it took for symptoms to develop, what symptoms you experienced and how long it lasted.
Your provider may order skin and/or blood tests to aid in making a diagnosis. However, a positive result on any one test is not an absolute indication of a food allergy. Allergists rely on their experience to properly interpret the results of tests within the overall context of the patient’s medical history and properly diagnose a food allergy.
If you suspect you have a food allergy, talk to your provider to determine what method of diagnosis is most suitable.