Health benefits of marriage uneven.

• Position: YOUR LIFE

Marriage may not always be as beneficial to health as "experts" have led us to believe, according to a study published in the Journal of Health and Social Behavior. Researchers made two discoveries that explain why. First, marriage provides less protection against mortality as health deteriorates, even though it does seem to benefit those who are in excellent health. Secondly, married people tend to overestimate how healthy they are compared to others.

"We believe marriage is still good for the health of some people, but it is not equally protective for everyone," notes sociologist and lead author Hui Zheng. "For those who are already in poor health, marriage doesn't seem to provide any extra benefits."

The results generally hold true for men and women. They also were similar for all types of unmarried people, including divorced, widowed, and never married. The researchers included separated couples in the unmarried category. They used data on about 789,000 individuals who participated in the National Health Interview Survey from 1986 to 2004. In this survey, participants rated their own health on a five-point scale (excellent, very good, good, fair, poor). Zheng used follow-up data to identify the nearly 24,100 people who died during that span.

The self-rated health measure has been found to be one of the best predictors of when a person will die in both the short and long term--even better than doctor diagnosis in some cases. The researchers used a statistical model to determine how self-rated health, marriage status, and other factors related to mortality risk.

Overall, they confirmed the volumes of previous research which have found that, overall, being unmarried--including never married, divorced, widowed, or separated---significantly increases the risk of death. For example, a never-married person who lists his or her health as "excellent" is two times more likely to die within three years than a similar married person in excellent health, but the new finding is that, as self-rated health declines (from excellent down to poor), the mortality advantage for married people diminishes. When individuals rate their health as "poor," there essentially is no difference in...