A food allergy is an immune system response. It occurs when the body mistakes an ingredient in food, usually a protein, as harmful and creates a defense system (antibodies) to fight it. Food allergy symptoms develop when the antibodies are battling the "invading" food. The most common food allergies are peanuts, tree nuts (such as walnuts, pecans and almonds), fish, and shellfish, milk, eggs, soy products, and wheat.
A food allergy is an adverse immune response to certain kinds of food. Food allergies are distinct from other adverse responses to food, such as food intolerance, pharmacological reactions, and toxin-mediated reactions. The protein in the food is the most common allergic component. These kinds of allergies occur when the body's immune system mistakenly identifies a protein as harmful.
Food intolerance is a digestive system response rather than an immune system response. It occurs when something in a food irritates a person's digestive system or when a person is unable to properly digest or breakdown, the food. Intolerance to lactose, which is found in milk and other dairy products, is the most common food intolerance.
Food allergies cause roughly 30,000 emergency room visits and 100 to 200 deaths per year in the United States. The most common food allergies in adults are shellfish, peanuts, tree nuts, fish, and eggs, and the most common food allergies in children are milk, eggs, peanuts, and tree nuts.
Milk and soy allergies in children can often go undiagnosed for many months, causing much worry for parents and health risks for infants and children. Many infants with milk and soy allergies can show signs of colic, blood in the stool, mucous in the stool, reflux, rashes and other harmful medical conditions.
A food allergy is an adverse immune response to a food protein.
Food allergies and food intolerances affects nearly everyone at some point in their lives. People who have food allergies must identify and prevent them because, although usually mild and not severe, these reactions can cause devastating illness and, in rare instances, can be fatal.
Food allergy is thought to develop more easily in patients with the atopic syndrome, a very common combination of diseases: allergic rhinitis and conjunctivitis, eczema and asthma. Treatment consists of either immunotherapy (desensitization) or avoidance, in which the allergic person avoids all forms of contact with the food to which they are allergic. People diagnosed with a food allergy may carry an autoinjector of epinephrine such as an EpiPen or Twinject, wear some form of medical alert jewelry, or develop an emergency action plan, in accordance with their doctor.
The best method for diagnosing food allergy is to be assessed by an allergist. The allergist will review the patient's history and the symptoms or reactions that have been noted after food ingestion. If the allergist feels the symptoms or reactions are consistent with food allergy, he/she will perform allergy tests.
In response to the risk that certain foods pose to those with food allergies, countries have responded by instituting labeling laws that require food products to clearly inform consumers if their products contain major allergens or by-products of major allergens.
Symptoms of food allergy include: