What's the key to long life? Is it clean living? Lots of exercise? An abundance of vegetables? Actually, the key to long life may be something a bit more intangible: a sense of purpose.
Researchers studying longevity say those who feel a sense of purpose and direction in life may indeed live longer, no matter what their age.
"Our findings point to the fact that finding a direction for life, and setting overarching goals for what you want to achieve, can help you actually live longer, regardless of when you find your purpose," said lead researcher Patrick Hill of Carleton University in Canada in a written release. "So the earlier someone comes to a direction for life, the earlier these protective effects may be able to occur."
Previous studies have suggested that finding a purpose in life lowers mortality risk above and beyond other factors that are known to predict longevity. But, Hill points out, almost no research evaluated whether the benefits of purpose vary over time, such as across different stages of a person's development.
In their research, published in Psychological Science, a journal of the Association for Psychological Science, Hill and colleagues examined data from more than 6,000 participants over a period of 14 years, focusing on their self-reported purpose in life.
Researchers say those who had died had reported a lower purpose in life and fewer positive relations than had those who had lived. Across the board, a greater purpose in life consistently predicted a lower risk of dying, showing the same benefit for younger, middle-aged and older participants. However, the sooner you discover a sense of direction and purpose, the better.
Researchers said they were surprised by the consistency.
"There are a lot of reasons to believe that being purposeful might help protect older adults more so than younger ones," Hill said. "For instance, adults might need a sense of direction more, after they have left the workplace and lost that source for organizing their daily events. In addition, older adults are more likely to face mortality risks than younger adults.
"To show that purpose predicts longer lives for younger and older adults alike is pretty interesting, and underscores the power of the construct," he explained. "These findings suggest that there's something unique about finding a purpose that seems to be leading to greater longevity."
Previous studies, too, have linked a sense of purpose with a longer lifespan. For example, one study from 2009 found that a person who derives meaning from life's experiences and possesses a sense of direction was about half as likely to die during a five-year follow-up period than a person who lacked a real purpose.
In another study, a sense of purpose was found to help protect the brain against the damage of Alzheimer's disease.
So what do you think? Got purpose?
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