Large weight gains most likely for men after divorce, women after marriage

Both marriage and divorce can act as “weight shocks,” leading people to add a few extra pounds – especially among those over age 30 - according to a new study.

But when it comes to large weight gains, the effects of marital transitions are quite different for men than they are for women.

For men, the risk of a large weight gain increased most prominently after a divorce. But for women, the risk of a large weight gain was most likely after marriage.

“Clearly, the effect of marital transitions on weight changes differs by gender,” said Dmitry Tumin, lead author of the study and doctoral student in sociology at Ohio State University.

“Divorces for men and, to some extent, marriages for women promote weight gains that may be large enough to pose a health risk.”

The probability of large weight gains following marital transitions increased the most for people past age 30.

“For someone in their mid-20s, there is not much of a difference in the probability of gaining weight between someone who just got married and someone who never married. But later in life, there is much more of a difference,” he said.

Tumin conducted the study with Zhenchao Qian, professor of sociology at Ohio State University. They presented their research Aug. 22 in Las Vegas at the annual meeting of the American Sociological Association.

While there have been many studies about weight gain after marriage or divorce, 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.

But these results may mask the fact that some people actually lose weight, while some stay the same and some have large weight increases, Qian said.

“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,” Qian said.

Tumin and Qian used data from the National Longitudinal Survey of Youth ’79, a nationally representative sample of men and women aged 14 to 22 in 1979. The same people were surveyed every year up to 1994 and every other year since then.

In this study, the researchers used data on 10,071 people surveyed from 1986 to 2008 to determine weight gain in the two years following a marriage or divorce.

The NLSY included data on Body Mass Index (BMI), a common health measure of weight relative to height.

The researchers separated people into four groups: those who had a BMI decrease of at least 1 kg/m2 (about 7 pounds for a person 5’10” tall) in the two-year period after a marital transition; those who had a small BMI gain (7-20 pounds for the 5’10” person); a large BMI gain (more than about 21 pounds); or no weight gain or loss (net change of less than 7 pounds).