How Your Job Complexity Could Protect Your Brain from Dementia

Getting an education is important for many reasons, but here's one you might not have considered: it could lower your risk of dementia later in life. Decades of research support this, with studies showing each additional year of formal education reduces Alzheimer's or other dementia risks by 7 percent.

Now, a growing body of evidence suggests the jobs we hold throughout our lives may matter just as much—or even 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.

"Many studies suggest that, if people are working in complex jobs during their lifetime, they have a lower likelihood of developing dementia in later life," said Jinshil Hyun, assistant professor of neurology at Albert Einstein College of Medicine.

Roles like managers, teachers, lawyers, and doctors are considered high-complexity jobs, while clerical, transportation, and assembly line work have lower complexity. These findings align with the idea that engaging in mentally stimulating activities throughout life 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 these criteria—there are other ways 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 at work, at least eight hours a day. 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 factors influencing education's protective effect against dementia. Their analysis included 384,284 participants and considered health behaviors, medical conditions, occupational complexity, and income. The results revealed that occupational complexity is the biggest reason more education tends to lower dementia risk, accounting for over 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 researchers speculate 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 predicts later-life dementia, independent of education. They examined dementia-free survival time in 10,195 participants from six countries. High school graduates had a 26 percent increase in dementia-free survival time compared to those with less education.

After controlling for education, high occupational complexity, compared to low, 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, helping people resist cognitive decline and stay mentally sharp longer, even with Alzheimer's-related brain plaques.

"The cognitive reserve hypothesis suggests that, if people are doing cognitively enriching activities, then their brain has a more efficient network," Hyun said. "Even if they have a significant amount of pathology in their brain, they have other pathways so that different parts of the brain can still communicate with each other."

What to Do If Your Job Isn't Particularly Complex

There are several other ways to strengthen your cognitive reserve beyond your occupation:

• Embrace lifelong learning. "Education increases cognitive reserve, like building a muscle," Mukadam said. Aside from reading regularly, look for classes offered by local parks and recreation departments or community colleges.
• Pursue enriching hobbies. Some leisure activities—like playing board games and craft activities such as knitting and quilting—have benefits for the brain.
• Find volunteer opportunities. Having a sense of purpose may help preserve cognitive function as we age, according to a recent study. Giving your time to a worthy cause can solidify that sense of purpose, teach new skills, and broaden your social network.
• Stay socially connected. Strong social connections are linked to greater cognitive reserve.
• Keep your brain engaged even after you retire. If your job is a source of enjoyment and not stress, Hyun advises against early retirement. "Retiring later may protect your cognitive health longer," she said.

"Cardiovascular health has been a concern for many, many decades, so it's great that people are now interested in what they can do for brain health," said Mukadam. "As we're living longer, it's important to preserve that brain function so we can continue to use our brains as long as possible."