Doing something that's good for your heart may also be good for your brain. It turns out that a class of cholesterol-lowering drugs known as statins may halve the risk of dementia in populations already at high risk. The exact mechanism is not yet known, but high cholesterol is a known risk factor for dementia, along with high blood pressure, diabetes, and obesity.
Another study has shown that autopsies of people who took statins before death showed fewer plaques and twisted nerve fiber tangles in their brains than people who did not. Yet another study showed that people taking angiotensin receptor blockers—blood pressure medication—had up to a 40 percent lower chance of developing dementia.
At the same time, a study performed by the University of Kansas Medical Center showed that patients in the early stages of Alzheimer's disease who performed cardiovascular exercises showed less progression of the disease than patients who did not exercise, possibly related to the fact that exercise can improve cholesterol and blood pressure.
The take-away from all of this, I think, should be that living a healthier life now can lower your risk of dementia and Alzheimer's disease in the future—especially given that mental decline that often precedes Alzheimer's disease is on the rise.