When the funny men of "Monty Python" first sang, "always look on the bright side of life..." they didn't know they were touting serious health advice.
According to a study in Health Psychology, optimism can have a seriously healthy affect on your body's stress level. Researchers set out to see how a sunny attitude affects stress by looking at a particularly stressed-out demographic — older adults.
"A lot of people think older adulthood is retirement, rest and relaxation," explained researcher Joelle Jobin, a PhD candidate at Concordia University. "But it's also a time that's marked by many age-related challenges, such as cognitive changes, an increase in chronic illness and the loss of loved ones — all associated with an increase in cortisol and stress."
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So for six years, Jobin and her team analyzed the stress perceptions and cortisol secretion in 135 adults over 60.
The results: Optimists had an overall lower baseline level of cortisol than pessimists. The optimistic folks also experienced a more stable pattern of cortisol levels throughout the day.
Why care about your baseline? Cortisol is secreted by everyone on a 24-hour rhythm, usually highest in the morning and decreases throughout the day. Certain conditions (like depression) are associated with a deregulation of the hormone. An increase in cortisol can impact your immune system, making it harder for your body to fight infection, puts you at risk for an autoimmune flare-up like shingles, and can make other diseases like cancer and cardiovascular disease progress more quickly.
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Optimists who had generally more stressful lives did experience a spike on cortisol just after waking up. But on days that were particularly stressful, pessimists experienced a much higher level of cortisol throughout the day, and had a harder time bringing it back down. "It's a stress hormone, but it's also our 'get up and go' hormone," Jobin explained.
Previous studies have had a hard time proving the biological advantages of optimism. The problem, according to Jobin, was the confusion between optimism and stress perception.
"If you think about it, an optimist during the day is more likely to see her environment as less threatening," she said, which explains why optimists had significantly lower perceptions of stress.
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While you can't really change your baseline cortisol levels — that starts developing in the womb — Jobin said you can prepare your body and mind for an influx of stress by staying positive. "If you believe things are going to turn out okay, your body won't experience the full effect of a traumatic event," she said.