If You're Stressed, There's Hope: Wait Until You Hit 50

If you're stressed by what life sometimes throws your way, wait a while. It gets better. Really.

As you age - especially once you hit 50 - personal contentment increases while stress levels fall, according to new research published in Early Edition, the online journal of the Proceedings of the National Academy of Sciences.

Researchers found very different patterns in changing measurements of well-being (such as enjoyment, stress, worry and sadness) as people got older. Those 50 and above experienced greater daily happiness and spent less time than younger adults feeling stressed and worried. Only one emotion - sadness.- tended to increase.

For Arthur A. Stone, a professor in the Department of Psychiatry at Stony Brook University who led the study, the biggest surprise was that "the age pattern from the life satisfaction (global well-being) was so different from the pattern for the negative emotions."

"That is new," he said in an email interview with CBSNews.com.

For more info: "A Snapshot of the Age Distribution of Psychological Well-Being in the United States," PNAS (Abstract)

Other researchers previously found well-being varies with age. But the new study measures both overall happiness (referred to as "global well-being"), and day-to-day feelings related to a subject's affective experiences or the impacts of outside events, such as stress (called "hedonic well-being"). The survey of more than 340,000 adults in the United States between the ages of 18 and 85 was carried out in 2008.

The survey was US-specific. Stone said future surveys would extend to other nations as well.

"We hope to ask these mood questions in other countries -- already the global well-being questions are available from a large number of countries," he said.

However, the researchers were unable to draw any connection between peoples' perceptions to material improvements in their lives and greater feelings of well being. After a lifetime of labor, the assumption might be that an average American's economic situation would be easier than when they were starting out. But the survey did not contain questions which might have allowed them to address that question, according to Stone.

88% of the respondents had high school educations while 29% had earned college degrees.

David Morgan contributed to this article.