(Xinhua)
Updated: 2008-02-05 06:56

LOS ANGELES - Happiness over the course of a lifetime follows a U-shaped curve and hits bottom at midlife, according to a study published Monday on the Los Angeles Times Website.

A team of US and British researchers, who set out to find the relationship between age and happiness, examined social survey data on 2 million people in 80 countries, and also took into account factors that affect happiness, such as divorce, job loss and income, before releasing the report.

According to the report, happiness reaches its lowest point around age 40 in women and age 50 in men in the United States while in Britain, unhappiness was greatest in men and women at age 44.

Andrew Oswald, one researcher from the group, said there's still a mystery around how happiness ebbs or rises, saying "there seems to be something inside human beings that is unexplained by life events."

But other researchers questioned the findings of the study. Richard A. Easterlin, an economist at the University of Southern California, said the study looked only at age, and did not answer the question that concerns people most.

"People want to know their prospects, what is likely based on their life circumstances," said Easterlin, who also studied the phenomenon of happiness.