Hearing loss affects millions of Americans of all ages. It can be caused by a genetic defect, an injury or illness, or result from repetitive exposure to loud noises or age.

But what really causes hearing loss? Tiny hair cells convert all sound information (a whistle, the wind rustling tree leaves or even a loved one’s laugh) into electrical signals that are sent to the brain. These hair cells look like regular hairs growing on your head, but are situated in the inner ear. For a video on how hearing works, and a diagram of the ear, visit www.hearinghealthfoundation.org/how-hearing-works.

Hearing loss happens when these tiny hair cells are damaged or die, and age, medications and injury are three causes for damage to these hair cells. Hearing loss is increasing in younger Americans, now affecting one in five teenagers, according to the Journal of the American Medical Association – an increase of 15 percent in the last 10 years.

Noise-induced hearing loss, which is 100 percent preventable, is also prevalent for veterans who have served in war zones, workers who consistently deal with loud machinery and even people who hunt or enjoy music. Specialist Rebecca Nava was deployed to Iraq in 2003 and served in many combat missions that involved artillery fire. Her hearing protection didn’t always stay in place when she was running and seeking cover during missions. When she was discharged in 2008, Nava complained to her husband about her ears ringing and having difficulty hearing. Now she wears hearing aids, but struggles hearing her professors during lectures. Nava recommends everyone protect their hearing before it’s too late.

Repetitive exposure to noises at 85 decibels or higher for more than 15 minutes per day – an MP3 player maxed out at full volume can emit 100 decibels or higher of noise – can cause long term hearing loss due to damage done to those tiny hair cells. Humans are unable to grow back these hearing hair cells. To learn more about the decibel levels of everyday sounds – and understand how loud is too loud – visit www.hearinghealthfoundation.org/decibel-chart.

To restore damaged hearing, Hearing Health Foundation is researching inner ear hair cell regeneration for humans through its Hearing Restoration Project. Researchers have discovered that birds and fish are able to spontaneously grow back these hair cells after they are damaged.

The Hearing Restoration Project seeks to accelerate research to find a cure for hearing loss in 10 years or less through increased funding. Visit www.hearingrestorationproject.org to learn more about the plan.

Hearing Health Foundation also provides information and reviews on topics like tools to enhance hearing, common noises that could affect long-term hearing and even reasons to get your hearing checked. To learn more visit www.hearinghealthfoundation.org.