It's graduation season, and new research offers yet another reason to congratulate someone who has completed at least nine years of education: They're likely to live longer.
An unusual, comprehensive study involving 1.2 million Swedes shows that students who were exposed to nine years of education rather than eight had a lower mortality rate after age 40. While the finding suggests an association between level of education and longevity, it does not establish a cause-and-effect link.
Those exposed to the additional year of education also had lower mortality from causes known to be related to education. The research, by Anton Lager of the Centre of Health Equity Studies and Jenny Torssander of the Swedish Institute for Social Research, both part of Stockholm University, was published in this week's issue of the Proceedings of the National Academy of Sciences.
Many studies have shown a link between more years of education and better health. But it has been difficult for researchers to show that the cause wasn't just personal characteristics, such as the ability to stick with school or delay gratification. It has also been hard to determine whether secondary benefits -- getting a better job or earning a higher income, for instance -- might be the reason why people with more education develop fewer health problems.