Allergy

Allergies are a wide variety of reactions by the immune system that occur through bodily contact with different foreign substances. Usually these kind of substances are seen as harmless (in non-allergic people), but by some immune systems these substances are recognized and so the immune system is turned on. Allergy-producing substances are refereed to as allergens (like: food, dust mine, pollens, and molds). Due to the presence of allergens that are unknown to the body, different allergic reactions occur. Allergic people usually react to allergens that seem quite harmless for non-allergic people. They usually experience allergic or atopic (allergic people are also refereed to as atopic) reactions.



To understand how allergies occur, we should first know the aim of the immune system. The aim of the immune system is to fight back antigens through the production of antibodies, or immunoglobulins like IgG, IgA, IgM, IgD, which are protective and destroy foreign substances by attaching to its particles (opening the way for the immune cells to destroy it). However, allergic people develop a peculiar kind of immunoglobulin called E, or IgE. IgE is an antibody which is found in everybody, but in small quantities. Nevertheless, in allergic people it is produced in waste quantities. The presence of such a large number of IgE, causes it to alter its affect from a normal antibody against parasites (but certainly not allergies) into explosive cells that contain chemicals, which in turn cause allergic symptoms and inflammation.