Overtime Is Bad for Your Heart Study shows that working late could literally kill you By Kevin Spak, Newser Staff Posted May 11, 2010 2:52 PM CDT 8 comments Comments For some weird reason, working too late seems to correlate to heart disease. (Shutterstock) (Newser) – Have you ever joked that the hours at your job will kill you? Stop laughing: you could be right. Those who work 10 or more hours a day are 60% more likely to develop heart-related problems, according to a new study in the European Heart Journal. That correlation held true even after researchers accounted for 21 other risk factors such as smoking, obesity, or high cholesterol. The study followed 6,014 people over 11 years, LiveScience explains. The researchers note that they haven't proved that work directly causes heart disease, only that there's a correlation. They theorize that stressed workers might suffer from frequent high blood pressure that wouldn't show up on medical check-ups, or that such hard workers might be more likely to work while ill, not get enough sleep, and put other stresses on their bodies.