With all the focus on gratitude and happiness today, you would think that a happy disposition would lead to a longer life, but that is also not true. In this study the kids who were described as "extraordinarily cheerful and optimistic," were in fact the ones who did not live as long. And those boring serious kids, the ones who worried about school and studied hard, who were conscientious and always worked? They lived the longest.
And the factor that best predicted long life? Work. Yes, work with all the stress and worry that goes with it. "It wasn't the happiest or the most relaxed older participants who lived the longest,... It was those who were most engaged in pursuing their goals." It seems that productivity and the sense of goal accomplishment is what keeps us going, not necessarily being happy. "This production orientation mattered more than their social relationships or their sense of happiness or well-being."
With several self-tests in each section to help you decide where you sit on the longevity continuum, The Longevity Project is an interesting study. Whether you agree with every conclusion the authors make or not, the information in itself will make you question your assumptions about how to live a long life.