Food allergies are one of many possible adverse reactions a person may have after eating a particular food. Symptoms of a true food allergy usually begin within a few minutes to an hour after eating. Delayed symptoms may be related to an additive or some other property of the food. Common symptoms may include rash, hives, swelling, nausea, vomiting, diarrhea, swollen lips or tongue, wheezing, asthma, and difficulty breathing. In extreme cases an individual may have anaphylactic shock (low blood pressure due to an allergic reaction) after eating a food. An anaphylactic reaction to a food can be fatal if untreated or undiagnosed. Patients, particularly children, may experience ongoing skin rashes (eczema) as a result of food allergies. The most common foods to cause allergic reactions include peanuts, nuts (almond, cashew, walnut, pecans, hazelnuts, Brazil nuts), milk, eggs, soybean, fish and shellfish.

Allergists, physicians who receive 2-3 years of additional specialized training in allergic diseases, provide care for patients with food allergies. Allergists can diagnose which foods have caused allergic symptoms and recommend the most up-to-date advice and treatments to treat and prevent reactions. Food allergies can be fatal. An accurate diagnosis and treatment plan is vitally important. The University of Michigan Food Allergy Service provides Allergists dedicated to taking care of the many needs of patients with food allergies.