I met a lady in her 90s who looks and acts the same age as her daughter, who is in her 60s. She lives independently, talks quickly, walks without a cane, and has a generally youthful appearance and demeanor.

I asked what her secret is to aging so well. "I don't know, just don't have any health issues, I guess", she said.

Maybe if you can make it that long without encountering Alzheimer's, Parkinson's, cancer, heart disease, osteoporosis, arthritis, or various other major issues... then you basically have a decent shot at still being fine and healthy at 94.