(Medical Xpress)—Social economists from the University of Melbourne have confirmed the age-old suspicion of a dip in human happiness during middle age.
Past evidence for "mid-life crises" have come from cross sectional data. That is, by comparing surveys of different people's happiness at different ages.
But now, for the first time, researchers have tracked the happiness levels of thousands of people across three countries over multiple decades.
"We have identified a clear 'U-shape' in human wellbeing," said researcher Dr Terence Cheng, from the University of Melbourne's Institute of Applied Economic and Social Research.
"The jury's now in. People really do experience mid-life crises."
The study—Longitudinal Evidence for a Midlife Nadir in Human Well-being—was completed in partnership with the University of Warwick and the London School of Economics, and published as a working paper by the German based Institute for the Study of Labor.
It used nationally representative survey data from Australia, Britain and Germany.
"What is interesting is the consistency of the results in all of the three countries we examined. Human happiness hits the lowest point around the ages of 40 to 42", Dr Cheng said.
"Indeed all the more intriguing is that the U-shape pattern has been recently observed in research on great apes. Perhaps we are more similar than we think?"
Dr Cheng said tracking changes in happiness over time makes the study more accurate.
"We looked at the well-being of 'Mr Jones' at age 35, 45, 55, and so on. This is important as the U-shape finding therefore does not arise from variations across different people, but rather within individuals," Dr Cheng adds.
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The study, "Longitudinal Evidence for a Midlife Nadir in Human Well-being," is available online: ftp.iza.org/dp7942.pdf