Working long hours may weaken mental skills, the BBC reports. Researchers administered a series of reasoning and memory tests to 2,214 British civil servants and found that those working more than 55 hours a week did significantly worse than those who worked around 40. The effect was cumulative, meaning the more hours over 55 employees worked, the worse their scores.
The researchers note that workers with long schedules reported sleeping less, drinking more alcohol and had symptoms of depression more often—all of which can adversely affect mental functioning. The effects of long working hours must be investigated further, one researcher said: “It is particularly important to examine whether the effects are long-lasting and whether long working hours predict more serious conditions such as dementia.”