Optimistic women less likely to die prematurely: study

There may be something to the old bromide about "the power of positive thinking."

A new study has found women who are more optimistic about their lives are less likely to die prematurely from chronic conditions such as cancer, heart disease, stroke, respiratory disease and infection.

Researchers at Harvard University's T.H. Chan School of Public Health analyzed the data of more than 70,000 women enrolled in the long-running Nurses' Health Study.

They reviewed self-reported levels of optimism in 2004 defined as "a general expectation that good things will happen" as well as other factors, such as mortality risk, high blood pressure, ethnicity, diet and physical activity. The same information was then gathered again in 2012.

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The biggest difference between the women who reported high levels of optimism, versus those who reported low levels of optimism, came in the form of high cholesterol and hypertension major risk factors for chronic disease. Eight to nine per cent fewer women who were the most optimistic had these conditions, compared to those who were the least optimistic.

Additionally, the optimistic women also had lower instances of Type 2 diabetes, cancer and stroke, and they smoked less and were more likely to have higher levels of education and physical activity.

Association isn't always causation

Research on the association between optimism and mortality is an emerging field, the authors say, and they're aware of only three other studies that examine the issue.

They admit data drawn from population-based studies can often lead to false conclusions about causation.

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They also acknowledge the risk of "reverse causation," for example, when people report low levels of optimism due to an underlying health condition. But the researchers say they attempted to avoid that mistake by excluding women who died within the first two years of the study or already had a serious chronic condition.

How to be more optimistic

The authors conclude that their research suggests fostering optimistic outlooks on life could be a "novel target" for future public health strategies, especially for older people.

And, they write, "optimism can be learned" through uncomplicated interventions. They point to randomized trials that showed improvements after a range of activities, including classroom instruction and simple "paper-and-pencil" exercises, in which people were asked to write about "the best possible versions of themselves."

Dr. Sarah Samaan, a cardiologist at The Heart Hospital Baylor Plano in Texas, agrees that healthy behaviours may help build optimism.

"It's easier to feel optimistic when you feel healthy and energetic," said Samaan, who was not involved in the research.

"By choosing a healthy lifestyle, you may open yourself up to greater gratitude and create more energy for deeper relationships and professional satisfaction."

The Harvard study was published in the American Journal of Epidemiology.