Most humans can tolerate substances such as dust, pollen and foods. However, for people who developed oversensitivity towards some substances (which are technically known as allergens), these substances become antigens that trigger the release of antibodies in the body for the protection of the immune system.
The particular antigen that is released after the exposure to an allergen is the gamma E globulin or IgE. This type of immunoglobulin is present in all humans to protect the body from parasitic infections. However, among those people who have allergic reactions to certain allergens, the IgE are produced in abnormally higher quantities.
There are various types of allergens which can be roughly divided into 6 categories namely indoor allergens, outdoor allergens, animal allergies, plant allergies, cosmetic allergies and drug allergies. The typical allergens to which a large portion of the population reacts to are the following:
Pollens- Pollens are known to contribute substantially to the incidence of perennial allergies. There are three common sources of pollens namely the tree pollen, the grass pollens and the weed pollens. People who are allergic to pollens often end up with hay fever. The most notorious pollens come from the ragweed which gives off its pollen sometime in August or September.
Molds- Molds are found in environments that are either hot or humid. The best candidates are the basement and the attic. If you have a perennial allergy, the culprit is most probably a type of mold that has been sitting inside your own home. Molds can become airborne, thus they can enter the nasal passages down to the lungs. This leads to allergic rhinitis, a very common type of allergy.
Dust mites- Dust mites are microscopic insects that thrive in the dust. Where there is dust, there are dust mites. Like molds, these enter your lungs, thereby causing the symptoms of allergic rhinitis.
Animal dander- Another common cause of allergic rhinitis, animal dander comes from the skin flakes that come off the animals. For people with allergic reactions to animal dander, it is advisable for them not to keep pets.
Foods- FDA recognizes 8 foods that typically cause allergic reactions to humans. This list is inclusive of eggs, peanuts, milk, tree nuts, shellfish, soy, wheat and sulphites (typical components of food colors and flavors). Eggs, especially the albumin that is found in the egg white, cause allergic reactions among children. Milk, especially cow milk and other animal milks, have protein components that induce allergic reactions among children.
Children normally outgrow their allergic reactions to milk and egg. Some protein compounds in wheat can serve as allergens to some people while fish and seashells, soy, tree nuts and peanuts that are ingested can cause immune response for some highly sensitive individuals.
Cosmetics and Fragrances- Allergens are also found in the chemicals that are used in cosmetics and fragrances. These trigger a host of reactions ranging from rashes to serious immune responses.
Drugs- Different people react to drugs differently. Like in cosmetics, there are components used in the production of drugs that do not work well with the immune system.
Allergens, regardless of the types, are basically products of mistaken identities. They are common foreign substances that are mistakenly identified by the body as threats, thereby reaction towards them are exaggerated.
Repeated exposure is very risky as it not only produces the allergic reactions but also aggravates the allergy reaction itself.
