For most people, getting married is one of the happiest events of their life. According to ABC News, after a few short years of marriage, a couple is twice as likely to become obese as couples who are just dating. Penny Gordon-Larsen is a professor of nutrition at the University of North Carolina at Chapel Hill, and she’s studied the relationship between romantic partnership and obesity. Larsen says there’s more and more evidence that people do indeed “let themselves go” after they tie the knot. Married couples are much more likely to be obese than couples who are dating - because they tend to watch a lot more television and not do much physical activity. Women usually gain more weight than men. Even women who live with their boyfriends - but aren’t married - increase their risk of obesity by 63%.

Why does this happen? Larsen says that once people are committed, they tend to focus more on their relationship – what it means to be a good wife or husband - than on exercising and looking good. Unfortunately, this isn’t just a vanity issue. Gaining too much weight harms your health. Still, there is good news. Amy Gorin is a professor of psychology at the University of Connecticut, and she says that marriage can work in your favor if one spouse decides to make healthy changes in their diet and exercise routine – because often, it’ll have a positive effect on their partner. An easy start? Gorin suggests cooking healthy meals at home, and walking after dinner instead of plopping down on the couch.