The number of people who are living to at least 100 years old in the U.S. has doubled over the past decade.
Many centenarians credit their longevity, at least in part, to their positive attitude.
Roslyn Menaker, 103, told The Guardian that "happiness, joy, appreciation … a positive outlook," are why she has lived so long. Ruth Sweedler, 103, told CNBC Make It that she was always praised for her good attitude growing up. "When I walked into a classroom, my teacher would say, 'Good morning, sunshine!' Because I was so cheerful," she said.
While seniors might feel being positive has played a role in their longevity, the relationship between personality and aging is more nuanced, says David Watson, a former professor of personality psychology at the University of Notre Dame.
"I think the effects of just being positive are overstated," he says. But there are other traits he believes are closely linked to longevity.
'Conscientious people don't do stupid things'
When breaking down personality, it's helpful to look at the Five Factor Model, a personality theory that suggests most people's traits can be grouped into five categories: openness, conscientiousness, extroversion, agreeableness and neuroticism.
Conscientiousness, or how organized and disciplined you are, is the most related to longevity, Watson says.
This is likely because people with high degrees of conscientiousness are better at taking care of themselves. Conscientious people, for example, tend to drink alcohol in moderation and eat more balanced meals, he says.
"Conscientious people don't do stupid things so they have lower rates of accidents and better health behaviors," he says.
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The good news is you can increase your conscientiousness with age. There are even conscientiousness workshops that seek to increase a person's ability to self-regulate, Watson says.
"The basic idea is if you want to increase your conscientiousness, act more conscientious, and the attitude follows the behavior," he says. "Try to be on time for things. Follow through on things."
This doesn't mean a positive attitude does nothing, he adds.
Agreeableness can play a part in longevity, too, especially when it comes to weathering stressful situations.
"Psychologically healthy people have a quicker recovery time," he says. "They are able to tell themselves, 'This is not that big of a deal.' They find ways to bring themselves back into that equilibrium."
If you're living a healthy lifestyle and able to bounce back from hardship, that, Watson says, could lead to having a longer, more satisfying life.
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