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About once a week, usually on my train commute home from Palo Alto, the person sitting next to me breaks that code of silence that is assumed by mass transit commuters and inquires about what I do for a living. When I tell that individual that I am a social scientist and study longevity, the response is almost always the same. “Ooh, so what IS the secret to longevity?!”
I usually rattle off a few of the things we know for sure are beneficial for longevity: Sit less, exercise regularly, keep learning new things, eat lots of fruits and vegetables, etc. I get lots of nods. Then, I usually talk about those things that psychologists and social scientists get especially excited about—social factors. And this is typically when people tilt their head with a puzzled look, or stop me with some level of incredulity.
“Really?!”
It may be surprising, but your social status and social life may be even more important for longevity than how much you exercise and how well you eat, in part because who you know is correlated to what kind of lifestyle you have. Who you choose as a friend matters, and so does the quality of those friendships. Good relationships have a potent beneficial impact on your health.
If you assume that exercise and nutrition are key precursors to the fountain of youth, you’re not totally wrong. But, if you look at the people who share smoothie recipes, and run into each other at the gym and the farmer’s market, they have a lot more in common than just what they eat and how much they move. As you might guess, they are much more likely to have higher-than-average education, more money, and jobs that are not particularly physically demanding. They know the same kind of people, make the same kinds of decisions, and benefit from the same social networks. While social class conclusively shapes longevity differences in the United States (Olshansky et al, 2012), regardless of whether you serve food cooked in coconut oil or butter at your dinner parties, people in other cultures still have an edge—even if they don’t go to the gym or drink sugar-free, gluten-free, vegan protein shakes.
Studies examining the longest-lived cultures around the world demonstrate that, while none eat much processed food and all maintain a relatively active lifestyle, they vary greatly in the types of foods they eat (though all eat lots of fruits and vegetables), and the amount and types of physical engagement they engage in. What isn’t different, however, is that their lives center on meaningful social relationships and purposeful living.
It seems that the most adaptive social network is one that offers an optimal balance of social relationships that provide close emotional support and an adequate amount of stimulation, challenge, and social engagement.
How do you know if yours does? If the people in your life support your personal goals, particularly when those goals are defined by a clear purpose in life, you might be on the right path. And we seem to make better decisions about these people as we age. We become more selective about the people we make time for in our lives as we get older, saving our time for those who provide the most positive emotional experiences (English & Carstensen, 2014).
Consider a culture that exemplifies these characteristics—and also happens to be home to the longest-lived people in the world: In Japan, and in Okinawa in particular, life expectancy is higher than any other place on Earth, with an astonishing number of centenarians. In fact, children born in Japan can expect to live about a decade longer than kids born in the United States. Efforts to understand the unique longevity benefits of the Japanese way of life have led many to consider an important factor often neglected in other cultures—Ikigai, which translates roughly to "life purpose." Living a life that centers on life purpose has the great benefit of bringing meaning to one’s life and daily activities, and shaping who you include in your daily life. This is particularly evident later in life. In the United States, retirement is defined primarily by what we don’t do (i.e., work). But in Japan, as older people negotiate their daily activities and who they spend their time with, the concept of ikigai clarifies their social role, providing the blueprint for an active, social, and productive lifestyle (Carr, 2013).
Having a life in which one focuses on meaning and purpose is likely protective in several ways. One hypothesis is that having a clear sense of purpose allows us to tolerate unpleasantries better because we can justify the benefits that may accrue in the name of a larger purpose beyond our own individual discomfort. In other words, while a certain task may not be particularly enjoyable, if you know that task is helping someone else or “doing good” for society, it feels justified and you can be resilient to temporary feelings of frustration, anger, discomfort, or sadness (Charles & Carstensen, 2008; Hershfield, Scheibe, Sims, & Carstensen, 2013).
But managing negative feelings more effectively isn’t the only reason why living a social, and meaningful, life likely has such a profound influence on our longevity. There seems to be a biological change that occurs physiologically, and while we don’t yet know all of the mechanisms, we are discovering some important potential pathways. For example, recent research shows that older people who volunteer have lower levels of inflammation—a factor linked to most chronic illnesses, as well as accelerated frailty and mortality (Kim & Ferraro, 2014). Why? Perhaps it is because volunteering is typically meaningful, and helps us meet and cultivate relationships with others who share our values.
So how do we know if we are maintaining meaningful social relationships and living a “purposeful” life? There isn’t one right answer, to be sure. But I like to ask people this question to help them consider their own life: Outside of your family, how many people would you be willing to call in the middle of the night if you needed help, and how many would be willing to get out of bed and come rescue you? And: What if you met one of your important life goals? Who would you call?
If you don’t have at least two people on both of your lists, perhaps you should take more seriously the role of social relationships in your life. And, if you don’t have any clear life goals from which to evaluate the way you spend your time and who you spend your time with, perhaps you should step back and take stock. If you pick the right friends, they could play a crucial role in your longevity.
So choose carefully…
References
Carr, D. C. (2013). Embracing the Japanese approach to aging. Next Avenue, http://www.nextavenue.org/article/2013-05/why-we-need-embrace-japanese-….
Charles, S. T., & Carstensen, L. L. (2008). Unpleasant situations elicit different emotional responses in younger and older adults. Psychology and Aging, 23, 495-504. doi:10.1037/a0013284 [PMID: 18808240] [PMCID: PMC2677442]
English, T., & Carstensen, L. L. (2014). Selective narrowing of social networks across adulthood is associated with improved emotional experience in daily life. International Journal of Behavioral Development, 38(2), 195-202. doi: 10.1177/0165025413515404
Hershfield, H. E., Scheibe, S., Sims, T., & Carstensen, L. L. (2013). When feeling bad can be good: Mixed emotions benefit physical health across adulthood. Social Psychological and Personality Science, 4(1), 54-61. doi: 10.1177/1948550612444616 [PMID: 24032072] [PMCID: PMC3768126]
Kim, S. & Ferraro, K. (2014). Do Productive Activities Reduce Inflammation in Later Life? Multiple Roles, Frequency of Activities, and C-Reactive Protein. The Gerontologist, 54(5):830-9. doi: 10.1093/geront/gnt090.
Olshansky, J. S., Antonucci, T., Berkman, L., Binstock, R. H., Boersch-Supan, A., Cacioppo, J. T., Cames, B. A., Carstensen, L. L., Fried, L. P., Goldman, D. P., Jackson, J., Kohil, M., Rother, J., Zheng, Y., & Rowe, J. (2012). Differences in life expectancy due to race and educational differences are widening, and many may not catch up. Health Affairs, 31(8), 1-12. doi:10.1377/hlthaff.2011.0746 [PMID: 22869659]
