According to the National Institutes of Health, an estimated one-third of Americans between the ages of 65 and 75 and close to one-half of those older than 75 have some degree of hearing loss. According to the Mayo Clinic Staff, doctors believe that there are two main factors that contribute to hearing loss over time. They are heredity and chronic noise exposure to loud noises. If you feel that you are not hearing as well as you should, start the new year out right by having your hearing tested.