Analyses of two large studies suggests that an optimistic outlook is about as good for you as diabetes or heart disease is bad.
I’m optimistic that you’ll find this week’s study particularly interesting.
Appearing in the Proceedings of the National Academy of Sciences, researchers from Boston examined whether higher levels of optimism – that feeling that, somehow, things will be OK – are linked to longer lives.
To answer the question, they used two existing cohort studies: the Nurses’ Health Study – with around 10 years of follow-up of 70,000 women, and the Veterans Affairs Normative Aging Study – about 30 years of follow-up of 1400 men. At baseline, the participants were asked how strongly they agreed with statements like “In uncertain times, I usually expect the best” and “Overall, I expect more good things to happen to me than bad”. This generated an optimism score.
Higher scores were strongly linked to longer survival.
Like, really strongly.
In fact, women in the top 25% of optimism scores lived 15% longer than those in the lowest. Men in the top 20% of optimism lived 11% longer than men in the lowest 20%. These analyses accounted for demographics, health conditions, and depression.
This increase in life expectancy is about equivalent to the decrease in life-expectancy associated with having diabetes or heart disease.
Optimism was also associated with “exceptional longevity” – defined as living to greater than age 85. Women in the top quartile of optimism were about 50% more likely to make it to that milestone than the least optimistic women. Men in the top quintile were 70% more likely to hit age 85.
These relationships were attenuated quite a bit when the authors adjusted for health behaviors like smoking and eating a high-quality diet, but we need to be a little careful here. It’s possible that more optimistic people are less likely to smoke precisely because they are optimistic – optimistic people exert effort, while pessimists disengage. If that’s the mechanism, adjusting for something like going to the gym would mask the true benefit of optimism. Optimists believe going to the gym will work for them, so they go to the gym.
Of course, nothing in medicine really matters if it can’t be changed. It turns out that about 25% of optimism is heritable, based on prior studies.
But there are multiple studies that show that you actually can change individuals’ inherent optimism levels. Studies have used journaling, meditation, and even cognitive behavioral therapy to achieve this goal.
As physicians, we may we need to encourage our patients with the words of the great Eric Idle:
“Always look on the bright side of life.”
-Eric Idle, on the cross
After all, it may save your life.
This commentary first appeared on medscape.com