BOB DOUGHTY: Doctors do not know what causes asthma. Medical researchers believe a combination of environmental and genetic conditions may be responsible. Forty percent of children who have parents with asthma will also develop this disorder. Seventy percent of people with asthma also have allergies. Allergies are unusual reactions of the body's natural defenses to normally harmless substances or conditions.
Doctors have identified many of the things that may trigger, or start, an asthma attack. Triggers are things that cause an asthma sufferer's airways to swell, or increase in size.
Different asthma patients have different triggers. Allergens are one of the most common triggers. These impurities in the air cause allergic reactions. Some of the more common allergens include animal hair, dust, mold and pollen.
SHIRLEY GRIFFITH: Pollen is a fine dust that comes from grass, trees and flowers. Mold is a kind of fungus. It can grow on the walls or floors of homes. It is often in wet or damp areas like bathrooms, kitchens and basements.
The Environmental Protection Agency estimates that twenty-one percent of asthma cases in the United States have links to mold and dampness in homes.
Air pollution can also trigger asthma. Cigarette smoke is a major problem for asthma sufferers. So is air pollution from motor vehicles. Chemical sprays like air fresheners, hair spray, cleaning products and even strong beauty aids can trigger an asthma attack.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25