Alarming number of teens are losing some of their hearing
An alarming number of teenagers have lost at least some of their hearing, approximately one in five and the problem has increased considerably in recent years, a new national study has found.
For the research, the team examined information from the National Health and Nutrition Examination Survey, a long-running government health study.
The number of teens going through hearing loss has risen by approximately a third in the last 20 years. High-frequency hearing loss was more common than low-frequency. Most of the hearing loss was slight, but there was an increase in the prevalence of mild or greater hearing loss over time (3.5% to 5.3%, P<0.001), the researchers reported in the Aug. 18 issue of the Journal of the American Medical Association. Teenage girls demonstrated less hearing loss than their male peers in 2005-2006.
Supported by the responses, it was found how many hours per week the teens listened to their devices. Sound levels were then factored in, allowing the researchers to calculate daily and weekly sound exposures. Those results were compared to noise exposure limits, as recommended by the Centers for Disease Control and Prevention (CDC).
Research has show that just a little hearing loss can hurt a child's school performance, language development and social interactions, the researcher noted.
Experts recommend teenagers to protect their hearing by lowering the volume on their MP3 music players. 
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