Allergies include seasonal allergies, hay fever, pet, dust and mold allergies. Allergies reflect an overactive immune system. Allergic reactions are inappropriate, but otherwise normal responses of the immune system to substances that it identifies as posing a threat. In most cases, however, the things we encounter in our environment that prompt allergic reactions aren’t harmful, such as dog hair, pollen, dust and mold. But when someone has an allergy to one of these substances, his or her immune system treats the irritant as a foreign invader and produces antibodies to it. These antibodies induce immune cells to release inflammatory compounds including histamine, which in turn cause allergic symptoms.
Every time a person encounters that particular substance or allergen, he or she will have an allergic reaction. About 15 to 20 percent of Americans have allergic reactions to airborne substances, which trigger the classic condition known as allergic rhinitis. The pollen-induced variety of allergic rhinitis is usually called “hay fever,” or “seasonal allergy” (because it tends to peak in the spring, when pollen counts are high). Allergies to dust, mold and pet dander can also elicit allergic rhinitis.
The tendency to have allergies is often hereditary, although allergies to specific substances are not, as these are acquired by exposure to the irritant. Allergies and its symptoms usually develop by age 10 and peak in a person’s early twenties; allergies often become less severe or disappear in older adulthood.
Allergies do serve a purpose. Food allergies serve to keep us away from foods that would tend to unbalance our body chemistry. Environmental allergies similarly warn us about chemicals, or pollens that may be damaging to our health. Many individuals in air-polluted areas suffer from allergies, which represent nothing more than their bodies crying out for cleaner air. Continue reading