If you are over 40 and reading this in the office, you should probably take the rest of the week off after today.
That is the lesson to be drawn from new University of Melbourne research, which argues that working more than 25 hours a week harms the brainpower of adults over the age of 40.
Shinya Kajitani, Colin McKenzie and Kei Sakata, three economists, knew that stress impairs cognitive functioning and development. They also knew that working some hours rather than none can improve mental acuity. So they looked at the Household Income and Labour Dynamics in Australia data set, which monitored the economic, well-being and labour market data of about 25,000 Australians.
They found that for people above the age of 40 working less than 25 hours, turning up to their job improved their mental functioning. But beyond that, working led to decreases in memory, and verbal and spatial intelligence.
The connection between long hours and health problems has long been known. Working more than 55 hours a week can lead to a greater risk of heart disease, depression, stroke and diabetes.
But the research from Kajitani et al is one of the first times that the effect on intelligence has been measured. “In the middle and older age, working part-time could be effective in maintaining cognitive ability,” the researchers conclude.
A team of UK researchers at the New Economics Foundation, a think tank, argue that the optimal length of the working week is just 21 hours. “A ‘normal’ working week of 21 hours could help to address a range of urgent, interlinked problems – overwork, unemployment, overconsumption, high carbon emissions, low well-being, entrenched inequalities and the lack of time to live sustainably, to care for each other and simply to enjoy life,” the think tank argues. Families would be able to more equitably divide housework and unpaid care activities – looking after children and disabled family members, for instance. Then there’s Parkinson’s Law, jokingly penned by the historian Cyril Parkinson in the pages of The Economist, which runs: “Work expands so as to fill the time available”.
The moral of all this was captured by the Elizabethan poet Michael Drayton: “Not long youth lasteth, and old age hasteth / Now is best leisure, to take our pleasure.”
So stop reading this, leave the office and enjoy your life.
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