(CBS News) -- Life goes on . . . and on, and on . . . for a small, but rapidly-growing number of us. Scientists have yet to discover a genuine fountain of youth. Still, they are learning some important clues while looking in some unlikely places. Our Cover Story is reported now by Barry Petersen:
What's the secret to living a longer life?
Consider this: Scientists are now researching the way bees think. Yes, the way bees THINK, and altering the lifespan of microscopic worms in search of groundbreaking answers.
"What has happened in the last 20 years is really a dramatic breakthrough in our understanding that lifespan itself is quite changeable," said Gordon Lithgow, a molecular biologist at the Buck Institute for Research on Aging in Marin County, near San Francisco.
But before we get to the science, some essential life lessons from people who've already cruised into old age:
Ellsworth Wareham was born October 3, 1914. (That makes Dr. Wareham 97 years old.) He performed his last operation as a heart surgeon just three years ago. What's his recipe for longevity?
"I think one of the important things is a plant-based diet, which is another way of saying that you are a vegetarian," said Dr. Ellsworth.
Becky Beck's another super-senior. She misses neither a beat nor a stitch. "I am 98 years old and I have been quilting for about 70 years," she said.
What's HER secret? "I don't drink coffee, I don't drink tea," she said.
And if you want to catch up with 101-year-old Herb Wile, meet him at the gym. "The body is the temple of the Spirit of God, and the scriptures says keep our bodies healthy and well," Wile said. "If you have a healthy body you generally have a healthy mind and they go well together."
Herb Wile, Ellsworth Wareham and Becky Beck all live in Loma Linda, Calif., and they are all 7th Day Adventists - a Protestant denomination that emphasizes physical health as a vital pathway to spiritual health.
Dr. Gary Frazer conducted a survey comparing lifestyles of Adventists to non-Adventists. "The men were living about seven years longer, and the women about four-and-a-half years longer than their non-Adventist neighbors," Frazer said.
And how come? "We believe that there's about four or five different factors that we were able to identify," he said. "Being a vegetarian seemed to help. Being careful about your body weight, like, not being too thin or not being overweight. Interestingly, people who ate nuts four or five times a week, just small amounts every day, seemed to benefit. People who have never been a smoker. And the last one was, being careful with your physical activity, and being sure that you exercised vigorously three or four times a week."
But before you rush out and become a vegetarian - or a 7th day Adventist - there's another critical element that helps determine how long you'll live: Genetics.
In New York City some super-centenarians - living to 100 and over - are subjects of a study by Dr. Nir Barzilai, director of the Longevity Genes Project at Albert Einstein College of Medicine.
What's remarkable about these folks - all Eastern European Ashkenazy Jews - is that, while their lifestyles may not have been the healthiest, that just doesn't seem to matter.
"As a group they have been overweight," said Dr. Barzilai. "They have been smoking - 50 percent of them have been smoking. Only a few have been exercising. Because they have the genes that protect them, they do not have to work with the environment the way you and I should. "
Dr. Barzilai is in the vanguard of a growing army of researchers working to get a handle on how, and why, we age.
The fact is, advances in health care and pharmaceuticals are already extending lives. In 2010, there were more than 70,000 centenarians (people living to 100 and beyond). But glance ahead to 2050, and the projected number soars to 4.2 MILLION.