The old sitcom cliché of a svelte woman married to a rotund man may hold a secret to marital contentment, according to a new study that finds both partners are more satisfied in marriage when the wife is slimmer than the husband.

The findings suggest it's not either partner's overall weight that matters in keeping the couple satisfied; rather, what matters is the relative difference between the two.

Of course, said study researcher Andrea Meltzer, a graduate student in psychology at the University of Tennessee, body weight is just one of hundreds of factors that influence how happy people are in long-term relationships. But the suggests that women shouldn't put much stock in the societal notion that being skinny is a prerequisite for finding a guy, Meltzer told LiveScience.

"Really, women of any size can be happy with the right partner," she said.

Little women

In news that will come as no surprise to daters, earlier research has found that people looking for love strongly prefer thin partners. But there is little evidence of the effect of body weight on relationship satisfaction outside of the realm of first impressions over dinner and drinks.

Meltzer and her colleagues gathered data from a large long-term study of 169 newlyweds, all under the age of 35. Couples in which the wife was pregnant were dropped, leaving 165 couples in the study. The vast majority of the couples were Caucasian, and the average age of the husbands and wives fell in the mid-20s range.

Every six months for the first four years of their marriages, the volunteers filled out mail-in surveys about their marital satisfaction. They also provided information about their height and weight at marriage, which the researchers used to calculate body mass index, or BMI.

On average, the men in the study were overweight, while the women were normal weight, though there was a wide range of variation among individuals.The results revealed that when wives have lower BMIs than their husbands, husbands are more likely to be satisfied at the beginning of the marriage and stay that way. Wives with lower BMIs than their husbands became more satisfied with time. [6 Scientific Tips for a Successful Marriage]

Happy husband, happy wife

"We think that what might be going on is that physical attractiveness and weight is more important to men than it is to women," Meltzer said. "So we're seeing this effect occur through men, such that the husbands are more satisfied at the beginning of their marriage and then wives' satisfaction follows later. Because husbands are more satisfied, then their wives are more satisfied."

Because what matters in marital satisfaction is not overall BMI, but BMI relative to your partner, Meltzer hopes the findings will take some of the pressure to be thin off of women. But she doesn't advise cancelling wedding plans if you don't fit the small wife/large husband paradigm.

"Just because a wife is thinner than her husband doesn't necessarily mean that the couple will be satisfied, and they won't necessarily be dissatisfied if a wife is bigger than her husband," Meltzer said. "This is just kind of an average … There can be variations within that."

This article was reprinted with permission from LiveScience.

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