What can 1,500 Americans born a century ago, most of them long dead, tell us about the secret to a long life? Plenty, according to Howard S. Friedman and Leslie R. Martin, two psychologists who, in "The Longevity Project," mine an eight-decade research effort for answers to the kinds of questions that sent Ponce de León searching for the Fountain of Youth.
There are no magic potions on offer here, but many of the findings are provocative. The best childhood predictor of longevity, it turns out, is a quality best defined as conscientiousness: "the often complex pattern of persistence, prudence, hard work, close involvement with friends and communities" that produces a well-organized person who is "somewhat obsessive and not at all carefree."
The study was initiated in 1921 by Stanford University psychologist Lewis Terman, who asked San Francisco teachers to pick out their brightest students—most were about 10 years old—to help him try to identify early glimmers of high potential. Terman was most interested in intellectual achievement (his revision of Alfred Binet's intelligence scale produced the Stanford-Binet IQ test), but his interviews were so detailed that the results could be used as a basis for studying the respondents' lives in follow-up interviews across the years. Terman himself died in 1956, just shy of 80; after his death his work was picked up by others, with Mr. Friedman and Ms. Martin launching their portion of the project in 1990.
The study's participants, dubbed Terman's Termites, were bright students, but having a high IQ didn't seem to play a direct role in longevity. Neither did going on to an advanced degree. The authors suggest that persistence and the ability to navigate life's challenges were better predictors of longevity.
Some of the findings in "The Longevity Project" are surprising, others are troubling. Cheerful children, alas, turned out to be shorter-lived than their more sober classmates. The early death of a parent had no measurable effect on children's life spans or mortality risk, but the long-term health effects of broken families were often devastating. Parental divorce during childhood emerged as the single strongest predictor of early death in adulthood. The grown children of divorced parents died almost five years earlier, on average, than children from intact families. The causes of death ranged from accidents and violence to cancer, heart attack and stroke. Parental break-ups remain, the authors say, among the most traumatic and harmful events for children.
The Longevity Project
By Howard S. Friedman and Leslie R. Martin
(Hudson Street Press, 248 pages, $25.95)
"The Longevity Project" is short on actual statistics, asserting instead broad trends among its study subjects and leaving readers to search through footnotes and then track down published studies if they want to learn more. With its relatively small sample and retrospective design, it hardly reaches the level of large population-based scientific investigations like the Framingham Heart Study, which followed thousands of participants for decades to identify common factors that contribute to cardiovascular disease, or the Women's Health Study, a 10-year randomized, double-blind, placebo-controlled study of nearly 40,000 women age 45 and older.
Mr. Friedman and Ms. Martin do claim to have used accepted scientific-validation methods to confirm that their findings can be extrapolated for a general understanding of health and longevity. But their results are based mostly on sifting participants' self-reported data, with death certificates providing the only verifiable information: age and cause of death. Data on factors like genetic predisposition to disease weren't gathered.
Moreover, the study's subjects lived most of their lives in a dramatically different time, before AIDS threatened longevity and before medical advances such as angioplasty and the development of cholesterol drugs came along to improve life-span. The respondents were almost uniformly white children from middle-class families, so the results don't tell us much about the longevity of other groups. And many of the girl students did not go on to have careers, so "The Longevity Project" focuses on men when it discusses workplace matters and their role in long-term health.
The book offers quizzes so that readers can assess various qualities—such as sociability, neuroticism and the tendency to "catastrophize"—and compare the results with those of Terman's Termites. The respondents to the study who fared best in the longevity sweepstakes tended to have a fairly high level of physical activity, a habit of giving back to the community, a thriving and long-running career, and a healthy marriage and family life. They summoned resilience against reverses and challenges— including divorce, loss of a spouse, career upsets and war trauma. By contrast, those with the darkest dispositions—catastrophizers, who viewed every stumble as a calamity—were most likely to die sooner. (The book doesn't say by what margin; a study published in 1998 reported that men in the Terman group were 25% more likely to die by age 65 if they were catastrophizers.)
And what about those cheerful, relatively doomed kids? The authors tell us that, later in life, such children would be more likely than their peers to throw caution to the wind when it came to life-shortening habits like smoking, drinking and driving fast cars. The chipper types were also more likely to die from homicide, suicide or accident. Of course, the authors don't suggest telling happy kids to wipe the grins off their faces, but Mr. Friedman and Ms. Martin do make a case for instilling values such as forethought and purposefulness. Indeed, "The Longevity Project" is not just an exercise in numbers-crunching; its larger aim seems to be to improve public health by encouraging a society with more goal-oriented and conscientious citizens. Now that's a long-term project.
Ms. Landro writes The Informed Patient column for the Journal.