The percentage of teenagers suffering from hearing loss has jumped by a third in little over a decade. That is the conclusion of researchers writing in the Journal of the American Medical Association. They drew numbers from the government’s National Health and Nutrition Examination Survey. Adjusting for factors such as age, race, and exposure to infections that could damage the ear, they found a slow but significant rise in hearing loss.

The researchers were unwilling to jump to the conclusions most of us would draw from the results. While they acknowledge that hearing loss could be due to listening to iPods and other portable music players, they couldn’t rule out other factors ranging from exposure to loud noises to nutrition to exposure to toxins.

Hearing loss has been linked to slower language development, poorer performance in school, and lower self esteem. And social skills are dependent upon language so the long term impact most likely will be in progressively lower scores on communication tests and greater anxiety.

Although the researchers were unwilling to draw too many conclusions, let me venture into this area. For example, a previous study in Australia noticed a correlation between hearing loss and using a portable music player (such as an iPod or other music player). Another study in New York documented that more than half the college students were listening to these players above the recommended exposure. And we should also add that teenagers also go to loud concerts and other noisy events such as NASCAR races.

When you think about it, we shouldn’t really be surprised by these findings. Loud portable music players may not be the only reason for hearing loss, but they are certainly a significant reason. Parents need to tell their kids to turn down the volume.