If you made a Venn diagram for the non-genetic risk factors for heart disease and Alzheimer's, they'd basically be a circle.

Being worried about dementia but ignoring things like heart disease, diabetes, poor sleep, getting enough exercise, eating a health-promoting diet, etc. is like worrying about paying for retirement but refusing to save and invest.

There are a handful of high-impact habits that meaningfully lower your risk for the major killers people are worried about: https://www.barbellmedicine.com/blog/where-should-my-priorit...