Have you ever heard someone claim that cognitive decline or even dementia is inevitable as we age, and wondered if that doom-and-gloom statement is true? According to the data on cognitive decline and dementia gathered over the past several decades, it is not.

Dementia is an umbrella term that includes several different types of age-related cognitive decline. The subtypes of dementia include Alzheimer’s disease (AD), which is the most common type and probably the most well-known. Other types of dementia (Lewey-body dementia, frontotemporal dementia, and vascular dementia) are less common, less well-known, and are associated with different characteristics and causes than those seen in AD.

There are roughly 6.7-6.9 million older adults (65 and up) with AD in the United States (as of 2025), which is 11 percent of the 61 million older adults in the USA (Alzheimer’s Association Report, 2025). In an online survey, 31 percent of more than 4000 people said that AD was their most feared illness compared to cancer, stroke, heart disease, and diabetes (Tang et al., 2017).

AD is characterized by the buildup of what are known as amyloid plaques and neurofibrillary tangles in the brain, which change the way brain cells function and ultimately cause cell death. Exactly why, when, and in whom these brain changes will develop is still unknown.

The accumulation of amyloid plaques and neurofibrillary tangles does seem to be age-related, but not everyone who develops plaques and tangles will also develop AD. Some individuals develop plaques and tangles but do not show any cognitive decline.

The reasons for this seeming resilience are still unknown and are being........

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