Photo credit: Daniel Frese

by Daniel Fink, MD, Chair, The Quiet Coalition

Why am I writing about preventing dementia on a blog site dedicated to noise? Please let me explain.

Dementia is common in older people, increasing with age. It is something everyone fears. And it is seen as something random and almost inevitable as we age.

A recent study in JAMA Neurology getting lots of publicity, including in this report from CNN, showed a correlation between walking almost 10,000 steps a day and reduced risk of dementia, or walking about 6,000 steps a day at a fast pace, more than 40 steps per minute. The reductions are large–about 50% for 10,000 steps, almost 60% at the faster pace. Maybe dementia isn’t inevitable.

I caution that this study is observational and shows only a correlation. It does not establish causation, i.e., the study doesn’t demonstrate that walking will reduce the incidence of dementia, although that conclusion makes sense. Multiple research studies show that much of dementia is vascular in origin and anything that improves vascular health. such as health diet, exercise, and not smoking, may reduce the incidence of dementia.

Why am I writing about dementia? Just as people think that dementia is an inevitable part of aging, they think that hearing loss is also an inevitable part of aging. This is shown by the use of terms like “presbycusis” and “age-related hearing loss.”

But the evidence shows that just as dementia isn’t an inevitable part of aging, neither is hearing loss. Research done largely in the 1960s showed preserved hearing well into old age in isolated populations not exposed to loud noise. Occupational safety and health research correlates noise exposure with hearing loss, forming the basis of occupational noise exposure regulations. Thousands of animal experiments show that noise damages cochlear hair cells, causing noise-induced hearing loss. How noise exposure causes hearing loss is now understood down to the cellular, subcellular, and molecular levels.

Noise-induced hearing loss is the only type of hearing loss that is entirely preventable.

Walking faster for longer distances won’t prevent dementia entirely, but avoiding noise will protect your hearing.

Avoid loud noise, use hearing protection, or leave the noisy environment, and your hearing should last a lifetime.