Many of my patients over age 55 tell me that they don’t seem to be hearing as well as they used to. It’s not a dramatic loss of hearing but more like a fuzziness of sounds or missed words in conversation. They find themselves turning up the volume or asking people to repeat themselves more frequently. Although it’s annoying to them, they’ve written it off as just “getting older”. I always encourage my patients to become proactive with hearing difficulties to both improve it and/or prevent further decline. They’re surprised when I tell them the reason why. I’d like to share it with you as well.
Your Hearing Can Affect Your Thinking
Recently, researchers out of Johns Hopkins University revealed the results of one of their latest studies on hearing [Hearing Loss and Cognitive Decline in Older Adults Hearing Loss and Cognitive Decline in Older Adults. JAMA Internal Medicine, 2013; 1 DOI: 10.1001/jamainternmed.2013.1868]. In their groundbreaking study, they found that older adults who develop hearing problems are more likely to develop problems with memory and thinking too.
The participants underwent cognition (mental ability) tests over 6 years. At the end of the study, it was found that all of the participants with hearing loss had experienced 30%-40% decline in cognitive ability. Those people also underwent cognitive changes 3.2 years earlier than those without hearing problems – the level of decline related to the amount of hearing loss.
What’s the connection between hearing loss and mental decline? Well, the researchers had a few theories including:
- Social isolation. Loss of hearing may lead to social isolation. Loneliness has been documented in other research to be a big risk factor in cognitive decline.
- Tapped out brain energy. Hearing decline forces the brain to devote more of its energy to processing sounds, so it starts to “borrow” from cognitive areas of the brain, like memory or thinking, to assist with hearing.
- Underlying brain damage. Underlying areas of brain deterioration that may be contributing to the hearing loss.
What Causes Hearing to Decline as You Get Older?
I agree that all of the above theories could contribute to the connection between hearing loss and mental decline. There are also other reasons for suffering hearing loss including:
- Loud noise exposure
- Toxins (environmental, or medications like antibiotics)
- Ear canal infection
I’d also like to offer another more common cause of hearing loss – and even cognitive decline – in older people. Poor nutrition, or just not absorbing enough specific vitamins – particularly the B vitamins, folic acid and B12, can cause both hearing problems, memory and cognitive decline.
Many researchers around the world are coming to the same conclusion. Recent research out of the University of Pennsylvania’s School of Medicine revealed that age-related hearing loss may be linked to folic acid (B9) and B12 deficiencies. In their study, otherwise healthy people over age 60 with speech-frequency hearing loss had serum folate (folic acid) levels about 32% lower than similarly aged people with no hearing loss.
Another study published in the Journal of Neurological Science and the American Journal of Clinical nutrition revealed that supplementation with B6 and B12 improved hearing.
As for the cognitive decline, Australian National University has shown that older adults who took B vitamins – particularly B12 and folic acid – had greater improvements on long and short term memory tests than adults who did not take the vitamins.
Folic acid and B12 both have a protective effect on the very sensitive nerves of the ear. The nerves of the ear pick up sound and transmit them to the brain. Deficiencies in these nerve-protecting vitamins frequently accompany sensorineural hearing loss.
Folate also lowers homocysteine, a cause of inflammation in the nervous and vascular systems. Because hearing is attached to the central nervous system, high homocysteine levels could be contributing to hearing decline through inflammation of the nerve cells.
To make matters worse, past the age of 40, most people lose the ability to absorb B12 through the gut and can easily become deficient. Be sure your diet contains enough folate and B12-rich foods in general. Good folate rich foods include leafy greens like spinach, kale, mustard greens as well as orange juice, fruits, vegetables and fortified cereals. Good B12 rich foods include beef and fish. Be sure your multivitamin contains an array of all B vitamins as well.
Hearing loss should be considered an important factor in healthy aging. Paying close attention to your nutritional status, B-vitamin wise, may help preserve and/or improve your hearing, memory and other cognitive functions. It’s important to stay socially connected as well since loneliness can aggravate mental decline. Learning and doing new things frequently helps exercise your brain and keeps your thinking and memory sharp. Also, statistics show that only 15% of people who need them get hearing aids. Aids not only help you hear better, they allow you to live your life to the fullest.
Mark Rosenberg, M.D.
Hearing Loss Linked to Mental Decline n Elderly, http://www.webmd.com/healthy-aging/news/20130118/hearing-loss-mental-decline
Hearing Loss Accelerates Brain Function Decline in Older Adults, http://www.sciencedaily.com/releases/2013/01/130121161747.htm
Hearing Loss Linked to Folate, B12 deficiencies http://www.medpagetoday.com/Surgery/Otolaryngology/23698