Stress on the job may raise your risk of a heart attack.

European researchers came to that conclusion after looking at the experience of nearly 200,000 people who took part in 13 different studies. The scientists found that people with stressful jobs had a 23 percent higher risk of heart attack than those whose jobs weren't pressure cookers.

What does it take for a job to be stressful? Just working hard isn't enough. A stressful job has to combine intense demands and little control over decisions about the work.

By that standard, about 30,000, or 15 percent, of the people studied had stressful jobs. The researchers had, on average, about 7 1/2 years of follow-up information about the people who participated.

Previous research on the effects of job stress on the heart has given mixed signals.

The researchers from a bunch of European universities who did the latest study are pretty confident they're on to something with this one.

Why? This time around they were able put together a really large pool of data by combining previously published and unpublished studies.

The data allowed them to look at the effects of job stress with more "precision than has previously been possible," they wrote. The findings were published online by The Lancet.

Even so, the researchers acknowledge this analysis can't prove cause and effect because the original work they drew upon only observed people — and didn't assign them randomly to high-stress and low-stress jobs.

If you've got some downtime at work, there's a pretty good podcast on the details with Mika Kivimaki, an epidemiologist at University College London and lead author of the study.

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