Health: The Secret To Living Well Into Your Nineties And Beyond

By Stephanie Stahl

PHILADELPHIA (CBS) -- 100-year-old Nan Smith is front and center at her weekly exercise class.

At nearly 98-years-old Margaret Freund is the oldest student at Fordham University.

Louis Solomon, a vibrant 99-year-old, stays busy at home.

And Margaret Ricciardi recently had an art show at the tender age of 100.  Her new project is sculpting a 40 pound block of alabaster for a class she's taking.

They are a new breed of seniors, living on their own, well into their hundreds -- and the secret to their longevity -- staying busy and having a positive outlook on life.

"There's nothing that doesn't interest me," said Solomon.

"Do something that they can enjoy," said Freund.

"We are going, not only to 100, but to a healthy 100," said Dr. Nir Barzilai, an expert on aging.  He says keeping seniors healthy in their old age is key.

"A lot of my centenarians are healthy until the week they die," said Dr. Barzilai.

Age may slow their step, but their optimism keeps them going.

Psychologist Daniela Jopp says the mental and emotional state of seniors is essential to their vitality.

"If you are more positive and feel more happy about your life that also strengthens your immune system and vice versa," said Jopp.

Scientists predict living to 100 and beyond will soon be the norm.  But now, for this group, living each day better is what keeps them going.  Living longer is just the bonus.

"You got to think, you got to do and move," said Solomon.

"You don't sit home and just do nothing," said Ricciardi.

Along with having good genes, all these seniors say they don't smoke and are not overweight, proven factors in living a long life.