The Longevity Project: Surprising Discoveries for Health and Long Life from the Landmark Eight-Decade Study, by Howard S. Friedman and Leslie R. Martin (Hudson Street Press, New York, 2011)
In the early part of the last century, Dr. Lewis Terman began a long-term study of children identified by their teachers as particularly gifted academically. Although Terman was interested in intelligence and intellectual leadership, his study left behind a great collection of sociological data, which Friedman, Martin, and their colleagues have mined for information on the factors that predispose human beings to long and productive lives.
The authors expound at length on why the data and their studies are valid, and the results applicable to most people, not just intellectual geniuses. And the results—no surprise—are much more complicated than conventional wisdom would lead one to believe. So interesting and complex are the relationships that it would be an insult to the researchers to attempt to distill their findings in a simple review. But I will note a few items of interest.
- Conventional wisdom often confuses correlation with causation. For example, although it is commonly believed that happiness promotes good health, and vice versa, the relationship is not in either direction cause-and-effect. Rather, the same underlying factors promote both happiness and health.
- The best personality predictor of longevity—as children and as adults—was what the authors call conscientiousness: people who were prudent, persistent, dependable, thrifty, detail-oriented, and responsible.
It is not only that conscientious people have better health habits and healthier brains, but also that they find their way to happier marriages, better friendships, and healthier work situations. That’s right, conscientious people create healthy long-life pathways for themselves.
Another key factor is social network, but as usual, it’s more complicated than simple sociability. Being an extrovert, having many friends, and abundant social activity do not presage a long life. Sociability itself, the authors say, is “a wash.” An active social life is a two-edged sword; how it cuts depends on the quality of the friends and of the activities.
Social ties, however, are critical: having a large support network is directly correlated with longer life. Interestingly, feeling loved and cared for did not improve longevity, but helping and caring for others did.
- The death of a parent during one’s childhood, while difficult, had no measurable effect on longevity. Divorce, on the other hand, was devastating—although for severely dysfunctional and drastically unhappy families, divorce was sometimes the healthier path.
Parental divorce during childhood was the single strongest social predictor of early death, many years into the future.
- It is decidedly unhealthy to be a “Chicken Little,” seeing impending doom everywhere and interpreting misfortunes as larger than life. Good health is not simply a matter of thinking positive thoughts, but those who lived longer had the habit of thinking of downturns as temporary and viewing problems as limited and specific rather than long-lasting and pervasive.
- I quote the following because I was so excited to find in print what I have been saying all along about life expectancy, inspired by my genealogical research. The oft-expressed belief that our ancestors could only expect to live to age forty (for example) did not square with the many sixty- to ninety-year olds in my family tree. (Emphasis mine)
The average life expectancy of an American born around the time of the Terman participants (about 1910) was forty-seven years. The average life expectancy of an American born in recent years is about seventy-nine. Still, it is totally incorrect to conclude that today’s middle-aged adults will live many, many years longer in retirement than did their predecessors.
The error arises from the fact that the average life expectancy is computed from birth. For the Terman subjects’ generation, many children died at birth or shortly thereafter. Many others died of childhood diseases. The twentieth century saw tremendous advances [that led] to a dramatic plunge in deaths during infancy and childhood. So-called modern medical cures have played a relatively minor role in increasing adult life span, something most people do not understand.
- An active lifestyle is conducive to a long, healthy life, but the benefit comes not from forcing yourself to visit the health club three times a week or going for a daily run if those activities are miserable and boring for you. Get active, the authors say, but in ways that you enjoy and which will thus become not a chore but part of your overall pattern of living.
There is a dirty little secret known to health professionals that they do not usually much talk about. Let’s assume that you follow the recommendations of a health authority and get out there most days to go jogging, even though you would much rather be doing something else. Say you get ready, warm up, jog, and cool down for about an hour a day, which is a modest regimen.
Over a year, you will spend bout 360 hours doing this, and during 40 years (say, from age twenty-one to age sixty-one), you will spend about 14,400 hours. Assuming that most of us are awake for about 16 hours a day, this means that you would be spending the equivalent of about 900 days jogging. This is about two and a half years spent exercising.
How much longer would such an active person live? How many extra days of life would this diligent jogger gain in which to pursue other well-loved hobbies? We do not know for sure, but anything that increased average longevity by more than two and a half years in a generally healthy adult population would be considered a very large effect—a striking phenomenon. So, with two and a half years spent on the pavement, there is not likely to be much of a net gain in available time for our poor jogger. Anyone who exercised even more would gain even less, winding up with a net loss of time.
But it gets even worse. Note that in this contrived example, the unhappy jogger is trading away thousands of hours of youth for perhaps a few extra years in old age. ...
Of course, the real picture is somewhat more complicated. The jogger might really enjoy jogging and so might consider the time well spent. Or the jogger might be warding off a diagnosed tendency toward a debilitating chronic disease such as diabetes. Still, for many reasonably healthy and active individuals who are out running every morning because some advice list or some friend is pressuring them to try to improve their health, the results are not necessarily going to be what they expect.
Perhaps the best news from The Longevity Project is that most of the unhealthy tendencies the researchers identified from their analysis of the Terman data are within our power to change: they are attitude and lifestyle choices, and the time to get onto a healthy path is now. Of course it's better to start young, but the benefits are measurable at any age.
Across the life span, many predictors emerged as to who would do better and who would do worse, who would live longer and who would die younger. It was not good cheer or being popular and outgoing that made the difference. It was also not those who took life easy, played it safe, or avoided stress who lived the longest. Rather, it was those who—through an often-complex pattern of persistence, prudence, hard work, and close involvement with friends and communities—headed down meaningful, interesting life paths and, as we have illustrated, found their way back to these healthy paths each time they were pushed off the road.
The qualities and lifestyles cultivated by people on these long-life paths reflect an active pursuit of goals, a deep satisfaction with life, and a strong sense of accomplishment. That’s not to say that these people possessed a giddy sense of happiness—we described how cheerfulness doesn’t necessarily lead to a long life. But having a large social network, engaging in physical activities that naturally draw you in, giving back to your community, enjoying and thriving in your career, and nurturing a healthy marriage or close friendships can do more than add many years to your life. Together, they represent the living with purpose that comes from working hard, reaching out to others, and bouncing back from difficult times.