If you're putting in more than 55 hours a week at work, the chances are good that you're working toward having a stroke, researchers say. A study involving more than 600,000 people found that people who work that many hours have a 33% higher stroke risk and a 13% higher risk of coronary heart disease than people working 35 to 40 hours a week, the Guardian reports.

The researchers, whose study is published in the Lancet, say that the risk goes up with every hour worked on top of 40 a week, with those working up to 48 hours increasing the risk by 10% and those working up to 54 hours by 27%.

The study is the largest one ever to examine the link between long hours and heart health, although researchers couldn't identify exactly what was causing the increased risk, even after controlling for factors like smoking, reports the New York Times.

Factors like stress, poor diet, and lack of exercise account for much of the increased risk, researchers believe, making it important for people putting in long hours to take good care of themselves.

"Working long hours can involve sitting for long periods of time [and] experiencing stress, and leads to less time available to look after yourself," a Stroke Association spokesman tells the BBC.

He advises people worried about their stroke risk to have regular blood pressure checks. (Southern food is also terrible for your heart.)

This article originally appeared on Newser: Bad News for Those Who Work 55+ Hours a Week

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