Yes!
A few years ago, I had lunch with a friend and his 97-year-old grandmother. I was surprised how clear eyed she was and what a vibrant personality she had. Her memory of life events was remarkably distinct and immensely interesting, given the fact she had lived through ten decades of history. Now at age 102, she's losin' her mental faculties and needs care and drugs to keep it together. She made it pretty far though and had a decent life.
Another time I was day hiking in the nearby mountains with a friend, when the hill kicked my butt and I had to stop to rest. Consider retreating back down. Hiking down the hill was a married couple clearly in their mid-80's. They told me they'd hiked the loop, which was a bit higher and about three times the distance I'd trudged so far. And I'm much, much younger! I asked them how they could do that at their ages. They told me they walk five miles a day, every day, to stay in shape.
Both were quite an inspiration to me for being able to stay very active and alert, I gotta say. Some people do it.
On the other side of the coin, I know people in their 50's and 60's that are already showing signs of dementia and lack of reasoning. Going a bit visibly batty. Talked to many of them during the last 18-month election cycle. The common thread with them is that they spent a lot of hours watching political news on cable TV every day (won't mention the network
) and got most of their current worldview from Facebook and Twitter. Unable to read complete books anymore because books are usually over 140 characters.
Hubbard began showing signs of dementia in his mid-60's. (Read poster
cowboy's threads for incontrovertible evidence and anecdotes.)
Oh, well.
I've decided that good life habits probably help, but a lot of life is simply luck of the draw.