Many people work longer hours than the traditional nine-to-five, but could they be damaging their brainpower? A Finnish study of 2,214 middle-aged civil servants in the UK asked them to complete five standard tests of cognitive function at the beginning of the study, and again five years later. It found that people who worked 55 or more hours a week scored lower on a vocabulary test at the beginning and end of the study, and showed a greater decline in their problem-solving ability. The study took into account the kind of jobs the workers did, their education, and medical conditions like high blood pressure and heart disease. The employees who worked longer hours tended to have higher stress levels, slept less and drank more than those who worked fewer hours but even this did not fully account for their quicker rate of cognitive decline.
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