Now, a growing body of evidence suggests that the jobs we hold throughout our lives may matter just as much or more than years of education. Having a job that involves high levels of decision-making or creativity, rather than repetitive or manual tasks, could help keep the mind sharp and active.
Roles like managers, teachers, lawyers and doctors are considered high complexity jobs, while clerical, transportation and assembly line work have lower complexity. The findings are consistent with the idea that taking part in mentally stimulating activities throughout the lifespan can help preserve late-life brain health and boost cognitive reserve — the brain’s ability to cope with age- or disease-related changes.
But don’t worry if your job doesn’t meet the criteria — there are other things that you can do to improve your cognitive reserve, such as reading, socializing and volunteering.
Why work might be linked to dementia risk
“We spend most of our day in work, at least eight hours a day. So that’s like, a third of our time engaged in work, sometimes more,” said Naaheed Mukadam, professor of psychiatry at University College London. “That’s a large part of what our brain is engaged in and therefore will have a large contributory effect on cognitive reserve development.”
In a recent study, Mukadam and her colleagues investigated which factors could be influencing education’s protective effect against dementia. Their analysis included 384,284 participants and took note of health behaviors like drinking, smoking and exercise; medical conditions like hypertension and diabetes; occupational complexity; and income. The results uncovered that occupational complexity is actually the biggest reason more education tends to lower your risk of dementia, accounting for more than 70 percent of that link.
“We found that occupational complexity explained the biggest proportion of that relationship between education and dementia,” she said. “People who have more education tend to get into better paid, more complex jobs. Then, the benefits for their physical and cognitive health compound in that way.”
Multiple studies have found that those with higher income have a lower risk of dementia, and the researchers speculate that job complexity likely plays a major role in that relationship as well.
Similarly, Hyun and her colleagues found in a 2021 study that occupational complexity is predictive of later-life dementia, independent of education. They looked at the effects on dementia-free survival time, or how many years a person lived before being diagnosed with dementia, in 10,195 participants from six countries. As expected, high school graduates had a 26 percent increase in dementia-free survival time compared to people who only completed middle school or less.
After controlling for education, high occupational complexity, compared to low occupational complexity, was associated with a 19 percent increase in dementia-free survival time. Hyun speculates that the greater mental stimulation of a complex job builds cognitive reserve, which helps people resist cognitive decline and stay mentally sharp for longer, even in the presence of harmful plaques seen in Alzheimer’s-affected brains.
“The cognitive reserve hypothesis suggests that, if people are doing cognitively enriching activities, then their brain has a more efficient network,” Hyun said.
by Meeri Kim, The Washington Post/Seattle Times | Read more:
Image: iStock
