Contrary to popular belief, teenagers are not suffering hearing loss from listening to music with headphones on iPods and other iPod-like devices, according to new analysis that was released today. A group of Harvard Medical School scientists looked at data gathered by the National Health and Nutrition Examination Survey, a study that tracked over 2,500 adolescents from 1988 to 1994 and another 1,791 from 2005 to 2006. Exposure to loud music via headphones nearly doubled from the first survey to the second, but the results revealed no change in the prevalence of hearing loss from the early 1990s to the mid-2000s.
The authors of the analysis, which was published in Pediatrics, note that they have greeted their findings with some healthy skepticism. The scientists warn that hearing loss could still show up down the line. They contend that hearing loss might be cumulative and delayed, and therefore surface as the participants age.
The study seems to contradict an earlier analysis of the same data from a team of researchers at the Channing Laboratory at Brigham and Women's Hospital in Boston led by Dr. Josef Shargorodsky. Shargorodsky's team found a 31 percent increase in hearing loss rates over time. The different results could be due to a broader definition of hearing loss used in the earlier study.
In addition to documenting hearing loss, the original questionnaire revealed that nearly one fourth of youths are exposed to loud noise for five hours or more per week. It noted that African- and Mexican-Americans are less than half as likely as white teens to use hearing protection when exposed to loud noises, but that those differences were non-significant when adjusted for exposure to guns.