April 21 (HealthDay News) -- With age comes wisdom, and now new research suggests happiness tags along for the ride.

Surveys of Americans taken since 1972 suggest that plenty of older people are quite happy, with more than half of black men and women over the age of 80 saying they're "very happy," with older white men and women following suit.

Young people were far behind. Only a third of 18-year-old white men surveyed said they were "very happy," and 28 percent of white women did. Young blacks were even less likely to report being happy.

As for generations, those born between 1946 and 1964 were least likely to say they're happy. "Baby boomers are less content with life as a whole," said study author Yang Yang, an assistant professor of sociology at the University of Chicago.

Yang examined data from the University of Chicago's General Social Survey, which conducted face-to-face interviews with 1,500 to 3,000 people during each survey period. With some exceptions, surveys were taken annually from 1972-1994, and every other year after that.

Since 1972, the survey had asked Americans this question: "Taken all together, how would you say things are these days -- would you say that you are very happy, pretty happy or not too happy?"

In his new study, published in the April issue of the  American Sociological Review, Yang looked at trends in happiness across various ages and races from 1972 to 2004.

Happiness increased over time, rising to high levels when people were older even as they presumably faced health problems and the deaths of friends and family.

"I am surprised by the fact that older adults are able to maintain a high level of subjective well-being despite general declines in physical health," Yang said. That is "a paradox that deserves future research."

Yang was also surprised that general levels of happiness didn't grow over the years, even as America became a richer country. "Over time, the happiness level is quite stable," Yang said.

The survey results also showed that differences in happiness by gender, race and education level lessened as people aged.

Still, the gap between blacks and whites persisted in the most recent 10-year period, even as the happiness levels of men and women evened out, Yang said.

And what of the Baby Boomers and their supposed inability to be as happy as other generations? "This is probably due to the fact that the generation as a group was so large, and their expectations were so great, that not everyone in the group could get what he or she wanted as they aged due to competition for opportunities," Yang said in a statement. "This could lead to disappointment that could undermine happiness."

As for the seeming happiness of older people, there are plenty of theories. One explanation "has to do with the human tendency to make social comparisons: If people compare themselves to others and figure they're better off than some other people their age, they are likely to feel happier than if they think they're worse off than others," said Rosemary Blieszner, a professor of human development at Virginia Tech.

Perception may play a role in the big picture. Americans assume that older people are unhappy, because they seem to have "no exciting jobs, no passionate sex lives, and poor health and a lot of wrinkles," said Sonja Lyubomirsky, a professor of psychology at the University of California at Riverside.

The reality may be very different.

In another study in the same issue of the journal, University of Chicago researchers reported that, contrary to popular thought, older people do stay social as they age, often volunteering, attending religious services, and spending time with their neighbors.

SOURCES: Yang Yang, Ph.D., assistant professor, sociology, University of Chicago; Sonja Lyubomirsky, Ph.D., professor, psychology, University of California at Riverside; Rosemary Blieszner, Ph.D., alumni distinguished professor, Virginia Polytechnic Institute and State University, Blacksburg, Va.; April 2008,  American Sociological Review