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Marriage and divorce are weighty matters for both men and women, but whether they pack pounds on or drop them is gender-based, according to a new study.

Marriage and divorce are weighty matters for both men and women, but whether they pack pounds on or drop them is gender-based, according to a new study.

Researchers from Ohio State University found that, especially after age 30, men are more apt to gain large amounts of weight after a divorce. For women over age 30, adding pounds is a problem after they marry.

The research was presented this week in Las Vegas at the annual meeting of the American Sociological Association.

"Divorces for men and, to some extent, marriages for women promote weight gains that may be large enough to pose a health risk," Dmitry Tumin, lead author on the study, said.

He noted there's not much difference in the probability of weight gain between someone who never married and someone who just got married in their mid-20s. Later in life, though, "there is much more of a difference."

A release from Ohio State noted that many studies have looked at weight gain after marriage or divorce, but "most of them look at average changes in weight and find very small increases in weight after marriage and often small decreases in weight after divorce." It doesn't account for differences in demography and may "mask" that some lose weight "while some stay the same and some have large weight increases," said Zhenchao Quian, professor of sociology at Ohio State, another researcher on the study.

"We estimated the effects of marital transitions on the likelihood of weight gains or losses for different categories of people, allowing for the possibility that not everyone who goes through a marital transition has the same kind of experience," he said.

For the study, Tumin and Quian looked at data from the National Longitudinal Survey of Youth. The researchers used data collected from about 10,071 people who were surveyed from 1986 to 2008 to see how much weight they gained in the two years after a divorce. Among information the longitudinal study collected was the Body Mass Index ratio of weight to height.

They created four groups: Those who had a BMI decrease in the two years after marriage or divorce that was roughly equivalent to 7 pounds if one were 5-foot-10 inches tall, a small BMI gain of 7 to 20 pounds, a large BMI increase of about 21 pounds and no change of 7 pounds or more in either direction.

The considered pregnancy, poverty, socioeconomic status and education — all factors known to impact weight gain or loss.

Regardless of gender, those who married or divorced were more apt to have a little weight gain in the two years after a marital transition than those who had never married.

The study diverged from others that found divorce leads to weight lost, at least in the near-term. "Again, this may be because other studies have not separated people into age and gender groups and only used average changes in weight," Tumin said.

The study does not explain why men are more likely to gain weight after divorce or why marriage is more apt to cause large weight gains in women. But those findings fit other research on how marriage affects the sexes.

"Married women often have a larger role around the house than men do and they may have less time to exercise and stay fit than similar unmarried women," Qian said. "On the other hand, studies show that married men get a health benefit from marriage and they lose that benefit once they get divorced, which may lead to their weight gain."

Weight gain is more pronounced after age 30 and and the changes grow as people get older, the researchers said.

The study only looked at people for two years, so the results may change over the years.

"Joy and grief are strong emotions that can lead to an increase or decrease in appetite," Susan Heitler, a marriage counselor and writer for poweroftwomarriage.com, told Timi Gustafson for a blog on the Seattle PI. "Newlyweds often gain small amounts of weight because they're content. But in people who are newly divorced, depression can cause substantial weight gain."

"The study offers a new way to think about marital transitions, and also considers both weight gains and weight losses," Jeffery Sobal, a nutritional sociologist at Cornell University in New York, who was not involved in the new study, told MSNBC.

"Relationships between marriage and weight are complex and contingent upon many factors," Sobal said. "This study offers some new insights, although much remains to be understood about marriage and body weight."