From the Longevity Project:
“The best childhood personality predictor of longevity was conscientiousnessâ€”the qualities of a prudent, persistent, well-organized person â€¦â€”somewhat obsessive and not at all carefree.”
The benefits of a conscientious personality are obvious: These people are less likely to smoke and drink, or drive dangerously. Throughout life, conscientious people are less impulsive, and less depressed. The researchers found that the prudent died less from all causes, not just those related to dangerous habits. It appears the conscientious have higher levels of the neurotransmitter serotonin (a brain chemical boosted by antidepressants), which is linked to, the authors write, “many health-relevant processes throughout the body, including how much you eat and how well you sleep.”
Among the most counterintuitive of the findings is that cheerfulness can kill. The authors write: “[C]heerful and optimistic children were less likely to live to an old age than their more staid and sober counterparts!” They found that cheerfulness was as big a risk factor for premature death as elevated blood pressure and high cholesterol. There seemed to be several reasons. The highly social went to more parties where they smoked and drank, craving the buzz. They died from accidents. But Friedman and Martin say their research showed something deeper. Despite the belief that optimists enjoy better health than pessimists, this research found a dark underside to optimism. When everything is going great, the optimist soars. But when facing life’s difficulties, the optimist can feel defeated by the magnitude of the struggle that’s required.
A long, satisfying marriage is good for both partners’ health and longevity. But the researchers found that it is not the institution of marriage itself that conveys some kind of life-extending elixir. The participants who made long, happy marriages tended to be the people who were more stable as children and young people. The participants who ended unhappy marriages were less happy even before they chose a spouse. (And in a research aside that just begs for more follow-up, female participants and wives of Terman men who reported the highest frequency of orgasm during intercourse tended to live the longest.)
For those who contemplate retirement as decades filled with leisure and relaxation, The Longevity Project serves as a warning. As Friedman says, “fun can be overrated” and stress can be unfairly maligned. Many study participants who lived vigorously into old age had highly stressful jobs. Physicist Norris Bradbury, who died at age 88, succeeded J. Robert Oppenheimer as director of the Los Alamos National Laboratory, overseeing the transition of the U.S. atomic weapons research lab from World War II into the Cold War.
Friedman and Martin say it’s the kind of stress that matters. The bright boys selected for the study who ended up having low-status jobsâ€”streetcar conductor, baker, porterâ€”and whose careers did not match their early promise were far more likely to die before age 60 than their higher status counterparts. Success, even in challenging jobs with demanding hours and responsibility, is a tonic. (Ever notice that orchestra conductors and dictators tend to go on forever?)
What Never Say Die and The Longevity Project agree on is the salutary effect of work. Jacoby writes, “Being forced to work longer, or to think about developing new skills to augment an inadequate retirement income, might turn out to be an invigorating kick in the pants for boomers rather than a life sentence at hard labor.” Friedman and Martin write that an analysis of the activities and accomplishments of study participants during the 1980s, when most were in their 70s, and following what happened over the next two decades was dramatic. “[T]he continually productive men and women lived much longer than their more laid-back comrades. â€¦ It was not the happiest or the most relaxed older participants who lived the longest. It was those who were most engaged in pursuing their goals.”culture health science character longevity personality research