Do you notice that you (or a loved one) frequently ask others to repeat themselves? Does speech sometimes sound muffled? Is it difficult to understand words, or follow a conversation, particularly in noisy settings? Are there problems hearing certain consonants or high-pitched sounds, and is the TV or radio volume always set on high?

Hearing loss results in missed information, the appearance of ignorance, and ultimately tuning out. More than one in ten people in this country have some degree of hearing loss, but once we hit 65, the fraction increases to about one in three, and a whopping half of those 75 or older have age-related hearing loss (presbycusis). Unfortunately, most forms of hearing loss are irreversible.

Let’s review some anatomy. Sound waves pass through the outer ear and cause the eardrum to vibrate. The eardrum and three small bones of the middle ear make the vibrations bigger as they travel to the inner ear. There, the vibrations pass through fluid in the cochlea, where thousands of tiny hairs attached to nerve cells help to turn these vibrations into electrical signals. These are transmitted to the brain, which turns these signals into the sounds we hear.

Both aging and loud noise (including some concerts, wearing ear buds, firearms, carpentry and motorcycles) lead to wear and tear to the hairs and nerves in the cochlea, which means that they can no longer properly transmit electrical signals. In the middle or outer ear, hearing loss can be caused by ear infections, unusual bone growth, heredity, or tumors. (Some of these are issues that can be resolved by treating the underlying cause.) A ruptured eardrum can be caused by loud noises, sudden changes in pressure, poking an eardrum with a Q-tip or other object, or infection.

Additional risk factors for hearing loss include taking some medications (including the antibiotic gentamicin, some cancer drugs, and even Viagra), taking very high doses of aspirin, and illnesses like meningitis and sinus disease.

How loud is too loud? A whisper might be about 30 decibels, normal conversation 60, and loud dishwashers 75. The danger zone starts above 80 decibels. Heavy traffic is 85, motorcycles 95, rock concerts can be 110 plus, an ambulance siren 120, and firearms and firecrackers 140 plus. The longer the noise lasts, the greater the damage.

How is hearing loss diagnosed? A physical exam by your health care practitioner would look for infection, middle ear congestion, allergies, and other issues. An audiologist or ENT (ear, nose, and throat) doctor would conduct specific hearing tests.

Clearly, some types of hearing loss are preventable. Avoid loud noise. Turn the volume down when listening to music. Be aware of the risks of snowmobiles, jet skis, hunting, using power tools, and attending rock concerts. Wear earplugs or earmuffs, and get annual hearing tests.

Other preventative steps to take: Avoid smoking, which can impair circulation and affect hearing. Get regular exercise to help prevent health issues that can lead to hearing problems, like diabetes or high blood pressure. Have your ears checked for ear wax, which can be softened at home with an over-the-counter product like Debrox, or removed safely by a healthcare professional.

Hearing aid technology has taken enormous advances, with devices getting much smaller, and quality getting much better. Some types of hearing loss can benefit from surgery or cochlear implants. Please don’t ignore the signs of hearing loss, and take action to improve your (or your loved ones’) quality of life.