The US National Institute on Deafness and Other Communication Disorders (NIDCD) estimates that 15 percent of American adults have some form of hearing loss caused by excessive noise. Exact figures are hard to pinpoint, for two reasons:
Many people are unaware that their hearing has been impaired, because it often occurs slowly and gradually. Therefore, statistics that are based on surveys where people are asked about any hearing loss they may have are likely to underestimate the actual numbers. In addition, some people are reluctant to admit they have a hearing loss, to others or even to themselves. (The social stigma that used to be commonly attached to hearing loss, however, has largely disappeared.)
Some loss of hearing occurs normally with age; up to half of people over age 75 have impaired hearing. It is hard to separate the effects of normal aging from the increased
hearing damage caused by cumulative exposure to everyday noise
over the course of years.
Although hearing loss affects a greater proportion of the population over age 65, and the risk increases with age, note that 1/2 to 2/3 of those with hearing loss are under age 65.
Temporary or Permanent Hearing Loss?
You have probably experienced the change in your hearing perception that can happen after you've been in a loud environment. Once you're back in quieter surroundings, sounds seem muffled or muted, and your ears might ring. This is actually
temporary hearing loss.
Your ears have the ability to recover from occasional overexposure to noise, but if the noise is prolonged or repeated enough times, the damage becomes permanent. There is no way to repair the damage and recover the lost hearing (although future research could make this possible one day).