Good genes are a blessing that some should be grateful for, but they can help only so much. The rest, for better or worse, is all up to you.
Back in 1946, when the first baby boomers were born, it was easy to imagine some sort of magic pill that would promise, if not immortality, at least a very long, happy, and healthy life.
Darn, another hoped dashed. We are living longer, but not always healthier and happier. Given that the ranks of Americans age 65 and older are soon to swell -- from 13 percent to 18 percent by 2030 -- geneticists, physicians, and psychologists are hard at work figuring out what it takes to thrive into old age.
Maybe the wisest thing you can do is choose your parents -- be born into a long-living family. That helps, especially if you hope to live past 100, a happy achievement that seems to run in families. Paola Sebastiani, a professor of biostatistics at Boston University, says that researchers have found that centenarians "seem to have something in their genes" that allows them to live long and to stay relatively healthy until nearly the end. Centenarians present "an extremely complex problem involving many genes," she said. By studying these survivors' biology, scientists are trying to develop drugs -- some already being tested on mice -- to delay conditions that plague people in old age, such as heart disease, diabetes, high blood pressure, and arthritis, according to Judith Campisi, a biochemist at the California-based Buck Institute for Research on Aging. The goal is to help people age in a healthier way.
However, don't get your hopes up about living past 100, should you lack the right genes. Demographic experts had predicted that the proportion of U.S. centenarians would grow over the past decade, but they were wrong. Instead, from 2000 to 2010, the figure held steady: Only about one in 5,000 Americans reached age 100 or above.
For the other 99-plus percent of us, even the best genes will get you only so far. "Genes account for one-fourth to one-third of longevity," estimated Howard Friedman, a professor of psychology at the University of California (Riverside) and the coauthor of The Longevity Project, published this year. "That leaves well over half not accounted for."
Most of the rest, for better or worse, is up to you. "The importance of choices people make is in so many ways responsible for the quality of life in old age," said Charles Reynolds III, a professor of geriatric psychiatry, neurology, and neuroscience at the University of Pittsburgh medical school. "Many people think they should be entitled to a good-quality 25 years after age 60. Well, they're not necessarily entitled, but they can put the odds in their favor."
One way -- "the least speculative and the most obvious" -- is with exercise, according to Simon Melov, a Buck Institute biochemist. "More activity is better than no activity, and most people are not doing anything. They're just sitting there." Exercise, he said, reduces the risk of cardiovascular disease and perhaps even a decline in cognition. One needn't run a marathon. Gardening, walking, swimming, woodworking -- all of these are more active than just sitting.
OK, what else? "If people live in a healthy way, they can extend [their lives into] the late 80s," Sebastiani said. This includes a familiar list of don'ts -- notably tobacco, fatty foods, and sweets. Indeed, "some have suggested that diet can be helpful" in avoiding a deterioration in memory due to vascular disease, said Marie Bernard, deputy director of the National Institute on Aging, part of the National Institutes of Health.
The Institute on Aging is also exploring the possible benefits of a radically reduced intake of calories, which research has shown to cause many animals to live longer; a long-term research project has 218 human volunteers ingesting 25 percent fewer calories a day than usual for two years to study the impact on longevity.
Everyone is aware that they'll probably live longer if they exercise, eat right, and don't smoke. The trick is to get people to do what they know they should. The Buck Institute's Melov suggests mounting a government-sponsored campaign to get the message across, sort of an adult version of first lady Michelle Obama's "Let's Move" campaign for kids. This could include subsidies for gym memberships and certain types of healthy food as well as a publicity campaign similar to one that Australia waged in the 1970s. With heart disease rampant, its government plastered the country with the slogan "Don't be a Norm," using a cartoon showing an Aussie watching TV while balancing a beer on his belly. "There was saturation -- television, radio," Melov recounted. "It was akin to launching a war on a lifestyle. And the country saw a dramatic reversal of fitness over 10 years."
Although physical fitness is important, so is psychological fitness. "The word I like to describe successful aging is active aging," said geriatric psychiatrist Reynolds. "That means socially, intellectually, and spiritually." Research has shown that people who maintain connections to others -- whether through family, friends, or work -- remain healthier in old age. A study of centenarians found that they had a purpose to their lives -- volunteer work or taking care of grandchildren and great-grandchildren.
But these rules aren't universal. "Everyone ages differently," the National Institute on Aging's Bernard pointed out. "If people who have been lonely and isolated their whole lives, and we say they need to be out and socializing -- but it's not in their nature -- it could be more stress than benefit."
She touts the advantage of preventive care as a larger part of the U.S. medical system, noting studies that show a greater incidence of cancer, heart attacks, strokes, diabetes, and lung disease in older Americans compared with Europeans. Preventive care can even ease depression, a serious problem among the elderly, albeit one that medical professionals often dismiss as natural and not worth treating. Not so, according to Reynolds. Depression can be treated with medication or psychotherapy, thereby improving a patient's physical health. The benefits -- and the downsides -- flow in both directions. "Disability can beget depression," Reynolds said, "and depression can beget disability."
But depression should be distinguished from garden-variety worrying -- and here's a provocative finding: People who fret about things may live longer. "[A] moderate amount of worrying can be good," particularly for men, said Leslie Martin, a psychology professor at La Sierra University in Riverside, California. Research has shown that men who think ahead and plan -- and, yes, worry -- tend to fare better after their wives die. In fact, men who were worriers faced a 50 percent lower risk of dying within the next few years after becoming widowers than men who weren't worriers, Martin reported.
Possibly the reason is that, in many marriages, "the wife is the protector -- telling the husband to get the doctor's checkup, to eat healthier, to wear a seat belt," she explained. "If a guy does more on his own, it may serve him well." This could also explain why men who are happily married tend to live longer than men who aren't, while wedded bliss seems to have no effect on women's longevity.
But for children, surprisingly, happiness can be a curse. Cheerful and optimistic kids lead shorter lives, Martin said. That's often because they participate in riskier hobbies and sports, and are more likely to smoke and to drink too much. "They think, 'Nothing bad will ever happen to me,' " she said.
It's good news, then, that whether people -- even teenagers -- will age with grace lies in many ways within their control. Of course, one always has the chance of getting hit by a truck. The role of dumb luck inspires experts to counsel: Don't be too hard on yourself. As federal administrator Bernard put it, "People shouldn't blame themselves if their aging isn't going exactly as they want."
Hey, relax (but not too much). Maybe you'll live longer.