Putting in a lot of overtime may be doing more than merely stressing you out at work. New research out of Korea finds people who work more than a 40-hour week are far more likely to develop heart disease.
The research, based on an analysis of the medical records of 8,350 Korean adults, has associated clocking in more than eight hours a day with coronary heart disease, a narrowing of the blood vessels that supply blood and oxygen to the heart.
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“The longer hours employees worked, the higher their chances of developing coronary heart disease within 10 years,” said Dr. Yun-Chul Hong, senior author of the study, published in the American Journal of Industrial Medicine, “with those working 61 to 70 hours having a 42 percent increased likelihood of developing the disease, those working 71 to 80 hours having a 63 percent increased likelihood, and those working more than 80 hours having a 9 percent increased likelihood.”
The findings suggest individuals working 31 to 40 hours per week were far less likely to develop heart disease over the 10-year study period, perhaps because of lower levels of stress.
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