Being happy may help to avoid a heart attack, a new study suggests.

Researchers at Columbia University in New York rated the happiness levels of more than 1,700 adults in Nova Scotia with no heart problems in 1995. Trained nurses interviewed the 862 men and 877 women to assess their heart disease risk and measure negative emotions like depression, hostility and anxiety, as well as positive emotions like joy, happiness, and enthusiasm.

'You need time to recharge your batteries or else your heart won't be able to take it.'— Dr. Joep Perk

After a decade, they examined the 145 people who developed a heart problem and found happier people were less likely to have had one.

The study was published online Thursday in the European Heart Journal.

"If you aren't naturally a happy person, just try acting like one," said psychologist Karina Davidson of Columbia University Medical Center, the paper's lead author. "It could help your heart."

Davidson and colleagues used a five-point scale to measure people's happiness. They then statistically adjusted to account for things like age, gender, and smoking.

For every point on the happiness scale, people were 22 per cent less likely to have a heart problem. The study was paid for by the U.S. National Institutes of Health and others.

Happy benefits

Davidson said happy people were more likely to have a healthier lifestyle.

It could also be there is an unknown genetic trait that predisposes people to be happy and have less heart disease.

Other experts said happiness itself could result in a healthier heart, compared with other emotions such as stress or depression.

Stress often releases hormones that can damage heart muscle. Stress can also cause blood vessels to open too wide, allowing plaque buildups to break off and clog the arteries, according to Dr. Joep Perk, a professor of health sciences at Sweden's Kalmar University and spokesman for the European Society of Cardiology. Perk was not linked to the study.

"I often tell my patients not to get too depressed because it's bad for your heart," Perk said. "You need time to recharge your batteries or else your heart won't be able to take it."

Depression has long been noted as a risk factor for heart problems. Davidson said it was premature to draft guidelines recommending patients boost their happiness levels just to protect their hearts, even if it might help, until broader studies now under way are completed. But she does recommend trying to be happy for other reasons, like better mental health.

"Anything that patients can do to increase the amount of [happiness] in their lives will be helpful," said Davidson, who hails from Vancouver and began the research in 1995 while she was at Dalhousie University in Halifax.

There was a slight proviso. "No smoking, eating unhealthy food, not exercising or anything potentially damaging." she said. "That's the only trick."

With files from The Canadian Press