Mental Floss magazine rounded up 100 bits of advice from people who have lived 100 years or more. I don't think getting old necessarily makes one wise but they did have some great tips. Here are my favorite ten:
“I don’t care what you’re passionate about: maybe saving Dixie cup covers. But if you do it passionately, you’re alive.”
"Nobody else controls you."
“[Humor is] a life force, a way of surviving the difficulties of living.”
“We all remember how as children, when we were having fun, we often forgot to eat or sleep. I believe that we can keep that attitude as adults, too. It’s best not to tire the body with too many rules such as lunchtime and bedtime.”
"Don't compare. You'll never be happy with your life. The grass is always greener."
“Have lots of people in the house and lots of different kinds of people—young, old, black, white, people from all over the world. People have always energized me.”
“Do one thing each day that is just for you.”
"Don't look at the calendar. Just keep celebrating every day."
"I make myself go out every day, even if it's only to walk around the block. The key to staying young is to keep moving."
"Find your passion and live it."
Plus one I doubt is true, but I sure like the sound of it:
"The secret to longevity is ice cream.”
(I offer these mostly for fun and as food for thought, but in terms of writing these also might be useful for creating lively, appealing, energetic characters of any age.)