Working more than 25 hours a week?
Then you're doing your brain more harm than good. And if you're clocking up 60-plus hours a week, your brain is actually performing worse than if you didn't work at all. These are the findings of a Melbourne Institute of Applied Economic and Social Research study of 6500 Australians aged 40 and over.
Researchers used data from the long-term Household, Income and Labour Dynamics in Australia survey to ascertain how time spent working affects the cognitive functioning of middle-aged and older people.
They cross-matched the number of hours people worked with the results from tests of their working memory, linguistic skills, concentration and information processing speed. They found that cognitive function steadily increased for every hour worked up to 25 hours a week. For every hour worked beyond that, cognitive function steadily declined.
"This suggests that in order to maximise your cognitive function of people, part-time work is better," one of the researchers, Colin McKenzie, economics professor at Keio University in Japan, said. There were no statistical differences between the results for men and women.
Professor McKenzie said he was surprised how the exact number of working hours that is optimal for cognitive function was so clearly identifiable. "Most people work full-time in Australia. They're working a lot longer than the number of hours which we find the peak in work."
Nearly 8.2 million Australians work full-time, and a further 3.8 million work part-time, according to the latest Australian Bureau of Statistics figures. Most full-time employees work more than 40 hours a week. People in mining, construction and agriculture are most likely to put in more than 50 hours a week.
But their brains could be performing worse than those who don't work at all. The study found people who worked extremely long hours had poorer mental function than those who did no work. Professor McKenzie said this was because of the physical and psychological stress associated with working long hours.
"For cognitive functioning, working far too much is worse than not working at all," he said. "In the beginning work stimulates the brain cells. The stress associated with work physically and psychologically kicks in at some point and that affects the gains you get from working."
However, Professor McKenzie suspects working long hours isn't as damaging for people under 40. "My personal guess is that the recovery function of the brain in younger people is a little bit different," he said. "Younger people are more resilient ... to working longer hours on a continued basis."
The researchers suggested that rather than the ''use it or lose it'' argument that delaying retirement age could stave off the deterioration in cognitive ability, it could actually be a case of ''use it too much and lose it'' when it comes to brain functioning and work.
"[The study] results suggest that people in old age could maintain their cognitive ability by working in a part-time job that requires them to work around 20-30 hours per week," the researchers said.
Read more: http://www.smh.com.au/national/why-you-shouldnt-work-more-than-25-hours-a-week-20160415-go7ert.html#ixzz49ZonXgFM