A 2017 study by the University of Leicester is bad news for many drivers: spending more than two hours a day driving hurts your brain. One reason driving is bad for you is because it’s a sedentary activity, and being sedentary is hard on your overall health (particularly your cardiovascular system). But it turns out that driving also shuts down your brain. Subjects in the study actually lost IQ points when they regularly drove long distances (such as daily commutes). People who did little or no driving had less decline in their cognitive powers. Researchers theorize that in addition to the sedentary problems associated with lots of driving, driving causes stress and fatigue, and the link between stress, fatigue, and cognitive decline is fairly well established. If your daily commute requires two or more hours a day behind the wheel, it’s time to move closer to your work—or find a new job.