How to Live 100 Years

The study - sponsored by the National Institute on Aging, part of the National Institutes of Health - includes investigators from four U.S. research centers and one Danish one. The idea, says Dr. Thomas Perls, the principal investigator at the Boston University Medical Center location, is to figure out which genetic, environmental and behavioral factors contribute to longevity.

"When it comes to rare genetic variations that contribute to longevity, family [analysis] is particularly powerful," he says. "But just because something occurs in a family doesn't mean it is necessarily genetic. There are lots of behaviors and traditions that happen in families that play a role in longer life expectancies. We want to use these families to ferret out what these factors are." (Special Report: How to Live 100 Years.)

There's no denying that longer life expectancy is swelling the number of seniors - people over age 65 - in our population. But it's the fastest-growing subset of that superannuated group that proves the most interesting for researchers - those over age 85, in particular the centenarians born in the late 1800s, who have lived through the 1918 flu pandemic, the Great Depression and both world wars; have witnessed women's suffrage and the moon landings; and are still here, keeping up with world events during the Administration of the nation's first African-American President.

In the most recent Census, health officials predicted that by 2050, more than 800,000 Americans would be pushing into their second century of life. After the numbers from the 2010 Census are tabulated, some experts believe that figure will grow. By all accounts, these new centenarians are far from the frail, ailing, housebound people you might expect. In contrast, the majority of them are mentally alert and relatively free of disability and remain active members of their communities. They may simply represent a new model of aging, one that health experts are hoping more of us can emulate, both to make our lives fuller and to ease the inevitable health care burden that our longer-lived population will impose in coming decades.

Most people today fall prey to chronic diseases that strike in mid to late life - conditions such as cancer, heart disease, stroke and dementia - and end up nursing disabilities stemming from these illnesses for the remainder of their lives. Centenarians, on the other hand, appear to be remarkably resilient when it comes to shrugging off such ailments; they seem to draw on some reserve that allows them to bounce back from health problems and remain relatively hale until their final days.

Dozens of studies have investigated such individuals, with the goal of picking out the secrets to their salubrious seniority. Those analyses, however, have generally followed two separate if parallel tracks. The traditional approach has been to study the lifestyle and behavioral components of vigorous aging - the good habits, such as a healthy diet, regular physical activity and mental exercises that might keep the elderly vibrant through their golden years. The New England Centenarian Study, which includes 850 people entering their 100s, for example, has identified several behavioral and personality traits that seem to be critical to longevity, including not smoking, being extroverted and easygoing and staying lean.