Be happy. Live longer.
No, it's not that simple, but new research says happy lives are longer -- by 35%.
The study, published Monday in the journal Proceedings of the National Academy of Sciences, found that those who reported feeling happiest had a 35% reduced risk of dying compared with those who reported feeling least happy.
Rather than rely on recollection, as in past studies, this British study of 3,853 participants ages 52-79 rated their feelings at different times on one particular day. Five years later, researchers recorded the number who'd died and controlled for a variety of factors, including age, gender, health, wealth, education and marital status.
This approach "gets closer to measuring how people actually feel," says study co-author Andrew Steptoe, a psychology professor and epidemiologist at University College in London.
"Responses to general questions are influenced strongly by personality, by what people think they 'ought' to say and by recollections that might not be quite accurate," he says.
What's not clear, he adds, is whether happy feelings are the key to longevity or if it's something else causing extended life. "We can't draw the conclusion that the happiness is leading directly to better survival."
Researchers who haven't yet read the study say this link between a one-day measure and mortality is important.
"The fact that positive emotions in one day predicted survival is pretty amazing," says Sonja Lyubomirsky, a psychology professor at the University of California-Riverside. "We do know that happiness is associated with an extended life span. If we can get people to be happier, would that extend the life span? We don't know that yet."
Arthur Stone, a professor of psychiatry and psychology at Stony Brook University in New York, whose research on well-being has taken measures over the course of a day for several days, says the relationship between happiness and mortality "must be fairly robust" with results evident in just the one day for this 3,853-person sample.
And what if some were just having a bad day?
"A 'bad day' should weaken the relationship," Stone says. "If they had been able to measure several days one would guess that the relationship would be even stronger."
Laura Kubzansky, an associate professor at Harvard's School of Public Health in Boston, says the study "highlights the idea that if you're consistently distressed, it's probably worth paying attention to how you feel -- it matters for both psychological and physical health."
This study asked participants to rate feelings on a 1-to-4 scale at 7 a.m., 7 p.m. and a half-hour after each. "Generally, they were less happy when they woke up and most happy at 7 p.m.," Steptoe says.
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