If work is a constant stream of mind-straining challenges, delicate negotiations to keep everyone happy and bursts of creativity, then you’re lucky. Researchers have found that the more people use their brains at work, the better they seem to be protected against thinking and memory problems that come with older age. In a study of over 7,000 Norwegians in 305 occupations, those who held the least mentally demanding jobs had a 66 percent greater risk of mild cognitive impairment and 31 percent greater risk of dementia after the age of 70 compared with those in the most mentally taxing roles.

Dr. Trine Edwin, a geriatrician and postdoctoral fellow at Oslo University Hospital, said, “It really shows how important work is. It’s important to go to work and use your brain and to use your brain to learn new things.” Edwin and her colleagues examined the cognitive complexity of various jobs based on the amount of routine manual and mental work and the degree of analytical and interpersonal tasks they involved. Most people worked jobs with similar degrees of cognitive demands throughout their 30s, 40s, 50s and 60s, meaning that those who started work in less mentally stimulating jobs tended to remain in them, as did those who took on cognitively challenging positions from the off.

After the age of 70, the volunteers took part in standard memory and thinking tests and were classified as having either no cognitive impairment, mild cognitive impairment or dementia. Of those who had worked in the least cognitively challenging jobs, 42 percent were diagnosed with mild cognitive impairment, compared with only 27% who had worked in the most cognitively stimulating roles. Among the jobs ranked as most stimulating were teachers and university lecturers, according to a study in Neurology. Some of the least cognitively demanding jobs were those that involved repetitive manual tasks, such as road work, cleaning and delivering the post. Previous studies have shown that education has a significant protective effect against cognitive decline in old age. Part of the reason is that better-educated people are more likely and more able to lead healthier lives.

However, education also appears to build “cognitive reserve” – the capacity to improvise and find alternative ways of doing things – which may help stave off mental decline, much as physical exercise delays frailty. According to Trine, higher levels of education accounted for about 60% of the protective effect seen among people who did mentally stimulating jobs. “It means that education is very important, but it’s also what you do afterward: it’s how you use your brain when you are working. You are building your cognitive reserve at work by being cognitively active,” she said.

The results suggest that people who spend their working lives in less mentally stimulating jobs might benefit from further education and pursue more cognitively challenging pastimes outside work. “It’s not that you are doomed or you are not – we can empower people for their later cognitive health with education and tasks that are cognitively stimulating,” Trine said.