Just being middle-aged may lead to depression, with sufferers most vulnerable at age 44, USA Today reports. Studying more than 2 million people over 35 years led British and American economists to conclude that middle age is the nadir of lifetime happiness. "If you are finding life tough in your 40s, maybe it's useful to know this is completely normal," said one of the lead researchers.
The results held up for residents of 72 of the 80 countries under scrutiny even when researchers controlled for factors such as marital and socioeconomic status. Other researchers caution about tying happiness to biological age, saying the U-shape curve exists for some but not all countries. A Princeton economist says that elsewhere, “older people are really miserable relative to younger people."