Beginning or ending a marriage can take a toll on your waistline, a new study says. But exactly when you need to start loosening your belt may depend on your gender.
Women are more likely to gain weight after they get married, while men are more likely to put on pounds after a divorce, the researchers found.
"When you have these kinds of big life changes, your weight may go up," said study researcher Dmitry Tumin, a doctoral student in sociology at Ohio State University.
The chance of a large weight gain after a marriage or divorce was highest for those over age 30, the study showed.
Most people do not put on enough weight after marriage or divorce for it to have a significant impact on their health, Tumin said. But for a small percentage of the population, the weight they gain may pose health risks, he added.
The results will be presented today (Aug. 22) at the annual meeting of the American Sociological Association in Las Vegas.
Marriage, divorce and changing waistlines
Earlier work has found that, in general, people tend to gain a small amount of weight after marriage, and lose a small amount after divorce. However, these studies measured the average change in weight across groups of people.
The researchers thought: what if some people gain large amounts, while other lose large amounts?
The researchers analyzed survey responses from more than 10,000 men and women in the United States, tracking their weight and marital status from 1986 to 2008. Participants were between ages 22 and 29 at the start, and ages 43 to 51 at the end.
The researchers measured the amount of weight gained or lost in the two years following a marriage or a divorce. They defined a weight gain of between 7 and 20 pounds (for a person who is 5 foot 10 inches) as small, and a weight gain of more than 20 pounds as large. A large weight loss was defined as any drop in weight of more than 7 pounds.
Most participants' weight did not fluctuate much in the two-year period following a marriage or divorce. However, about 10 to 15 percent gained a large amount of weight after a marriage, and 10 percent lost weight after a divorce.
In a given two-year period, women who married were 46 percent more likely to gain a large amount of weight than women who remained unmarried. Men were not at increased risk for large weight gains after marriage, the study showed.
However, men were 63 percent more likely to gain weight after divorce than men who remained married over the same period. Women's risk of weight gain after divorce was about half that.
The chance of gaining weight was larger for men and women who married or divorced after age 30, and the risk was even larger in older people, the researchers said.
The researchers did not collect data as to the reasons behind their findings, but because married women often have a larger role around the house, they may have less time to exercise, said study researcher Zhenchao Qian, professor of sociology at Ohio State University.
In contrast, men are known to get a health boost out of marriage, perhaps because their spouses monitor their behavior and eating habits, Tumin said. They lose this benefit once they divorce.
The fact that older adults are more likely to gain weight after a marriage or divorce may be because, as people age, they become more settled in certain eating and exercise habits, Tumin said.
"As you get older, having a sudden change in your life like a marriage or a divorce is a bigger shock than it would have been when you were younger," Tumin said.
The study only looked at weight changes in the two years following marriage or divorce, and it's possible monitoring for a longer time may yield different results, Tumin said.
"The study offers a new way to think about marital transitions, and also considers both weight gains and weight losses," said Jeffery Sobal, a nutritional sociologist at Cornell University in New York, who was not involved in the new study.
"Relationships between marriage and weight are complex and contingent upon many factors. This study offers some new insights, although much remains to be understood about marriage and body weight," Sobal said.
Pass it on: Marriage or divorce can lead to weight gain, but most people don't put on enough for it to significantly impact their health.