Happily Ever Fatter? How to Avoid Post-Wedding Weight Gain

What Causes Post-Wedding Weight Gain

I had two important men in my life during the months leading up to my wedding: my loving fiancé, Jon, and my intense trainer, Jason. While I'd been a three-times-a-week gym-goer for a decade, now I was suddenly spending more time with Jason than Jon. Military-drill-style commands ("Drop and give me 20! One more!") rang in my ears instead of romantic sweet nothings.

It was thrilling to watch as speed, distance, and calories burned climbed higher on the treadmill while my dress size plunged. I even maintained the intensity of my sweat sessions on our Hawaiian honeymoon, hitting the gym at our resort. Once home from paradise, though, life took over and my routine relaxed. My portion sizes began to mirror my husband's, and I even started to follow his lead after dinner, treating myself to ice cream most nights. By our first anniversary I'd gained back every pound I'd lost, and then some.

Mine is a familiar story, as it turns out. Research suggests that "newlywed spread" strikes the majority of couples. "Transition in relationships influences weight," explains Maureen Murtaugh, PhD, RD, associate professor of epidemiology at the University of Utah in Salt Lake City. "It's a time when you need to pay special attention to how much you're eating and working out, before you wake up and think, Oh, no, I gained five pounds."

The average newly married woman piles on even more than that -- about nine extra pounds over five years compared with a single woman, according to a University of North Carolina at Chapel Hill study. At the same time, she's probably exercising less. A 2010 study of more than 8,000 people over three years showed cardiovascular fitness levels dropped in those who were wed, while single women and divorced men got into better shape. "It may have to do with the 'marriage market' theory," says study author Francisco Ortega, PhD. Married people may work out less because they're no longer concerned about looking good enough to attract a mate. Essentially, they think they can afford to let themselves go.

"When I was single, as soon as my jeans started getting tight, I'd diet and exercise," says Ali Norvell, 30, a librarian in Hendersonville, North Carolina. "Once I got married, I would just buy new jeans." Ali gained 25 pounds in four years after she and her husband said "I do" in 2005. "I had a moment of truth every year, and I'd lose some weight, but I always gained it back," she says. "I couldn't stay motivated."

Biology may be partly to blame. The emotional shift that comes with commitment can cause a change in brain chemistry, which may affect our weight, according to Helen Fisher, PhD, a biological anthropologist at Rutgers University in New Brunswick, New Jersey, who has conducted brain scans on couples in love. When you're dating, almost everything you do together is new and exciting. "Novelty drives up the dopamine system in the brain, and that gives you energy, which makes you more active and helps keep your weight down," Fisher says. In contrast, relaxing into a deep attachment to a mate has the effect of increasing oxytocin -- the "love drug" brain chemical that is linked to bonding -- in place of dopamine and its rush. Good-bye, Pilates reformer. Hello, husband-size portions and couch-potato cuddling.

But hormones are only part of the picture. The biggest weight-gain culprit is the change in lifestyle that happens after marriage. When couples merge households and finances, they have much to negotiate: where to spend Thanksgiving, who's going to scoop out the litter box, when to start a family.

"It's a huge adjustment," says Michelle Gannon, PhD, a psychologist and the founder of Marriage Prep 101 workshops in San Francisco. "Balancing 'we' time with 'me' time is a challenge for most newlyweds, especially women, who tend to prioritize their relationships over themselves. They are often likely to sacrifice exercise for hanging out with their spouse."

Your new husband may even encourage less-than-healthy habits. "When you're combining lifestyles, sometimes the less active one wins out," says Cheryl Forberg, RD, nutritionist for The Biggest Loser and author of the cookbook Flavor First. When your guy wants you to skip your morning run to sleep in with him, it's easy to roll over and give in.

Living together also changes women's eating routines, usually for the worse. "You're probably making more lavish meals," Fisher says. Plus, men just eat a lot. The average active man needs up to 3,000 calories a day, compared with an active woman's 2,200, and his metabolism is 10 to 15 percent faster, which means he can put away bigger portions and not gain an ounce. The next thing you know, your plate looks like his does and your clothes are getting tight.

When Anjani Webb, 25, a marketing professional in Greensboro, North Carolina, got married, she began to bulk up immediately. Ten pounds later she realized that her spouse's habits were making her pack on the pudge. On her own, Anjani was happy to make a turkey sandwich or heat up a low-cal frozen meal for dinner, but that didn't cut it with her husband. Soon she was eating mountains of spaghetti with him a few times a week, munching on crackers in front of late-night TV, consuming sugary sodas and tubs of popcorn at the movie theater. "We were sharing," she explains. "He didn't want a small popcorn or diet soda. It was easy to fall into his snacking routine."

That's a slippery slope, especially if you're also slacking off on your workouts. "You need to be aware of self-sabotaging thoughts, like, It's okay to eat this food, because my husband's eating it," says Judith Beck, PhD, author of The Beck Diet Solution. To combat the lure of bigger portion sizes or fatty snacks, she advises writing the following reminder in a pop-up on your smartphone and on strategically placed sticky notes throughout your house: "I can eat whatever whenever, or I can be thinner. I can't have it both ways."