There is an interesting study that went up on PubMed a few days ago. the abstract reads …
Objective: Conscientious individuals tend to experience a number of health benefits, not the least of which being greater longevity. However, it remains an open question as to why this link with longevity occurs. The current study tested two possible mediators (physical health and cognitive functioning) of the link between conscientiousness and longevity.
Method: We tested these mediators using a 10-year longitudinal sample (N = 512), a subset of the long-running Health and Retirement Study of aging adults. Measures included an adjective-rating measure of conscientiousness, self-reported health conditions, and three measures of cognitive functioning (word recall, delayed recall, and vocabulary) included in the 1996 wave of the HRS study.
Results: Our results found that conscientiousness significantly predicted greater longevity, even in a model including the two proposed mediator variables, gender, age, and years of education. Moreover, cognitive functioning appears to partially mediate this relationship.
Conclusions: This study replicates previous research showing that conscientious individuals tend to lead longer lives, and provides further insight into why this effect occurs. In addition, it underscores the importance of measurement considerations.
The first most obvious thought is that it should of course be obvious that those who are conscientious will in all probability follow and adhere to, good health guidance, and will not only ensure they take sufficient exercise each day, but also strive to have a good diet. In other words, the folks who have the self-discipline, carefulness, thoroughness, and organization to pay attention to health guidance will live longer, but is this really true, does conscientious actually cause longevity, and if so, then how exactly does conscientious mediate longevity?
This link is not new news, it has been previously observed and known for some time. Previous research showed that conscientiousness (social dependability) in childhood predicted longevity in an archival prospective cohort study of bright children first studied by Terman in the 1920s. In 95 there was a study that suggested that the protective effect of conscientiousness was not primarily due to accident avoidance and could not be mostly explained by abstinence from unhealthy substance intake. They instead suggested that conscientiousness may have a more wide-ranging effects on health-relevant activities.
Now what makes this latest study interesting is that it appears to be leaning towards cognitive function rather than better implementation of health practices as the mediator between conscientious and longevity. Note I say leans towards, because this is not conclusive, its just one step along the way. Untangling the knots of many interrelated correlations in such complex things as human beings isn’t easy, so while the conscientiousness and longevity relationship is not new, what we do now have is further insight into how this relationship occurs.
To place the study in context,it is a subset of the long-running Health and Retirement Study of aging adults being run by The University of Michigan in which they survey more than 22,000 Americans over the age of 50 every two years, and have been doing so since it launched in 92. They collect information about income, work, assets, pension plans, health insurance, disability, physical health and functioning, cognitive functioning, and health care expenditures – net effect is a huge pool of data that may then be mined by studies like this one. The full scope of the program is described in the publication Growing Older in America: The Health and Retirement Study.