The rate of hearing loss among adults is dropping, despite the prevalence of iPods and other portable media players, according to a new study.
In the first study of long-term changes in hearing loss in 20th century adults, scientists found that the rate of hearing loss actually decreased for adults born progressively later in the century.
For every five years later a man or woman was born, their chance of incurring impaired hearing dropped 13 percent and 6 percent, respectively, according to the study (.pdf).
Why? Two reasons, according to the study: better overall health and reduced noise levels at work in the last 50 years.
In other words: cubicles are far less noisy than Industrial Revolution-era factories, despite popular use of personal headphones.
Led by Weihai Zhan of the University of Wisconsin, researchers analyzed hearing loss in more than 2,000 people living in Beaver Dam, Wisconsin, a small town in between Milwaukee and Madison. The scientists conducted three health screenings per person at five-year intervals.
The study also reinforces the notion that hearing loss is just as strongly affected by environmental factors as genetic traits. The findings were published in the January issue of the American Journal of Epidemiology.
