Working long hours may alter brain structure research suggests

Working 52 hours or more per week may alter the structure of the brain, research suggests.

Experts found that being “overworked” may affect those parts of the brain related to problem-solving and memory, while also potentially affecting mental health.

The findings, published in the journal Occupational And Environmental Medicine, looked at the impact of overwork on specific brain regions in health workers who regularly clocked up a 52-hour week or more.

Researchers drew on data from a long-term study looking at worker health and used MRI scans to examine brain structure.

Some 110 workers were included in the final analysis, most of whom where clinicians.

Of these, 32 worked excessive weekly hours, while 78 worked standard hours.

Those putting in long working hours every week were significantly younger, had spent less time in work and were more highly educated than those clocking up standard hours.

The researchers, including from Yonsei University in South Korea, said: “Overworked individuals exhibited significant changes in brain regions associated with executive function and emotional regulation.”

Analysis showed a 19% increase in left caudal middle frontal gyrus volume in the overworked group compared with the non-overworked group.

This part of the brain has a major role in various cognitive functions, particularly in the frontal lobe.

It is involved in attention, working memory, and language-related processing.

Other areas involved in attention, planning and decision-making were also changed according to the scans, plus regions involved in emotional processing, self-awareness and understanding social context.

The team concluded: “This study provides preliminary evidence that overwork is associated with structural brain changes, particularly in regions linked to cognition and emotion.

“These findings provide novel neurobiological evidence linking prolonged working hours to structural brain changes, emphasising the need for further research to understand the long-term cognitive and emotional implications of overwork.

“The results underscore the importance of addressing overwork as an occupational health concern and highlight the need for workplace policies that mitigate excessive working hours.”

Ruth Wilkinson, head of policy and public affairs at the charity the Institution of Occupational Safety and Health, said: “Global analysis from the World Health Organisation and International Labour Organisation has found that working long hours is on the increase and is responsible for about one-third of the total estimated work-related burden of disease.

“We believe urgent action is needed to tackle an epidemic of long working hours.

“A long hours culture can be experienced in what we’ve identified as the ‘small print’ of working life today.

“This captures those hidden or unspoken expectations placed on top of workers’ contracts.

“It includes always having to be available/on duty in this digital age, stripped of the right to disconnect from work outside of normal working hours….

“Our YouGov survey, last year, showed that nearly a quarter of UK workers regularly work more than the legal maximum people should work in the UK (48 hours a week), while 44% said working more than your contracted hours is part of the culture in their organisation. More than half said they regularly check work emails and messages outside of working hours.

“We want to see employers strip away the ‘small print’, identify and tackle psycho-social risks as part of risk assessment processes and become more transparent in how they treat their workers.”

Published: 14/05/2025 by Radio NewsHub