WEDNESDAY, Jan. 30 (HealthDay News) -- People around the globe hit the height of their misery and depression in middle age, a new international study suggests.
The finding by British and American researchers was based on an analysis of well-being among approximately 2 million people in 80 nations. With few exceptions, the observation appears to apply across the board, regardless of gender, culture, geography, wealth, job history, education, and marriage or parental status.
"The scientific fact seems to be that happiness and positive mental health follow a giant 'U' shape through life," said study author Andrew J. Oswald, a professor of economics at Warwick University in Warwickshire, England. "For the average person, it's high when you're 20, and then it slowly falls and bottoms out in your 40s. But the good news is that your mental health picks up again, and eventually gets back to the high levels of our youth."
Oswald and his U.S. colleagues will outline their conclusions in an upcoming issue of the journal Social Science & Medicine.
The finding was based on the pooling of several different sources of happiness data, including: two multi-decade happiness/satisfaction surveys (first launched in the 1970s), involving about 500,000 American and Western European men and women; four rounds of the 80-nation "World Values Survey" conducted between 1981 and 2004 in North America, Eastern and Western Europe, Asia, Africa, Australia, and Central and South America; and a 2004-2007 survey involving nearly 1 million Britons.
The bottom-line: For most people throughout the world, the highest probability for depression striking is around 44 years of age.
In the United States, however, some as-yet unexplained gender differences were observed, with happiness among men dipping the most in their early 50s, whereas women hit their nadir around the age of 40.
The researchers cautioned that cheerful people tend to live longer than unhappy people -- a fact that might have skewed the overall finding. But they also suggested that evidence of a happiness curve might simply reflect a midlife choice to give up long-held but no longer tenable aspirations, followed by a senior's sense of gratitude for having successfully endured while others did not.
"That said, some might find it helpful simply to understand the general trends of mental health as they go through their own life," said Oswald. "It might be useful for people to realize that if they are low in their 40s that this is normal. It is not exceptional. And just knowing this might help."
Dr. James S. Goodwin, director of the Sealy Center on Aging at the University of Texas Medical Branch in Galveston, agreed, suggesting that the finding is a testament to the notion of the value of age and experience.
"It's a very hard lesson for us to learn that happiness is not tied to the things, such as wealth, that we think it's tied to," he noted. "At the same time, there's no doubt in my mind that wisdom and knowledge increase with age, and that just gives older people more control over their lives. A lack of control, like someone in midlife worrying about their teenage kids going out for a drive, is the cause of a lot of distress. But usually that does go away. Eventually. And what replaces it is experience with how to control your temper, deal with grief, cope with intimidation. And that knowledge can lead to a more positive outlook. And greater happiness."
For more on depression, visit the U.S. National Institute of Mental Health.
SOURCES: Andrew J. Oswald, Ph.D., professor, economics, department of economics, Warwick University, Warwickshire, Great Britain; James S. Goodwin, M.D., director, Sealy Center on Aging, University of Texas Medical Branch, Galveston; 2008, Social Science and Medicine