Why do couples gain weight after marriage? How can you lose it if you both love to eat and hate to exercise?
Married people may gain more than 5kg than unmarried individuals. However, in the long run, those who are married are less likely to be at risk of major weight gain than those who remain single, according to Singapore study.

The average weight gain in the first year of marriage is about 1.63kg. (Photo: iStock/Pongtep Chithan)
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Starting a relationship does interesting things to you. You get that warm feeling (and it’s not because the air-conditioner has broken down) whenever you think of or see your special person. Your Whatsapp usage and handphone storage start to resemble your 16-year-old niece’s 24/7 texting and busted iCloud limit.
But love does more than make you behave like a giggly teenager. The erratic mix of anxiety, obsession and nervousness that lovebirds experience is courtesy of a spike in the stress hormone cortisol and concurrently, a drop in the mood-regulating neurotransmitter serotonin, according to the Harvard Mahoney Neuroscience Institute. That floaty, on cloud-nine feeling? That’s dopamine, nature’s antidepressant, flooding your brain when you’re in the throes of a new relationship.
As for physical changes, the most significant that many couples experience is weight gain. After all, those extra calories from after-office drinks, late-night supper deliveries, weekend brunches and home-cooked feasts with the fam (you know, to meet the folks) have to go somewhere – especially when you haven’t been hitting the weight deck as often as romantic dates.
And that’s before saying “I do”. According to Dr Annabelle Chow, a clinical psychologist from Annabelle Psychology, getting married is associated with greater weight gain and a higher likelihood of major weight gain (more than 5kg) than remaining unmarried, she said, citing this Singapore study.

“The transition into marriage (in the first year) is associated with an increase of about 1.63kg,” she said, with more women than men hitting this average weight increase, according to the study. Incidentally, men tend to gain an average of 0.4kg in the first year of marriage. “However, in the long run, those who are married are less likely to be at risk of major weight gain than those who remain single,” she said.
WHY THE WEIGHT CHANGE?
So why are we likely to, in the immortalised words of Frozen, let it go after marriage? Happy couples may be less motivated to maintain their weight when they don’t need to attract another mate, concluded researchers in another study. Interestingly, young newlyweds, who weren’t as satisfied with their relationship, tended to gain less weight. So, it may not be all bad if your partner has put on a kilo or two.
“I think that it is great that couples feel a sense of trust and bonding with their partners, to the extent that they can enjoy their relationship without worrying about usual societal expectations of looking great,” said Dr Chow.
And sometimes, the habits of a healthy partner can rub off on the other party, said Associate Professor Asim Shabbir, the director of National University Hospital’s (NUH) Centre for Obesity Management and Surgery. “A healthy partner can be of influence and motivate the other to change their lifestyle for the betterment of the family. For others, this may not be the case and both can succumb to obesity,” said Assoc Prof Shabbir, who is also the head and a senior consultant at NUH’s Department of Surgery.
Dr Chow agreed that the post-wedding weight change can go either way. “For example, you may be comfortable around your partner and do not mind your weight as much,” she said. Or “your partner may be into sports and you might tag along as it’s enjoyable. Consequently, you may end up losing weight, despite being a happy couple”.
LOSING IT TOGETHER
If you’re tired of going up a clothes size year after year, the good news is, you can lose the extra kilos as a team – yes, even if your favourite activity is checking out new eating places on weekends. Here’s how you can couple up to beat the extra calories.
1. Your favourite shared activity is checking out new eating places and food trends
Wanting to lose weight doesn’t mean you have to give up your interests, said Terri Chen, the head and senior principal psychologist with NUH’s Psychology Team at Department of Psychological Medicine. “This can still be done in moderation. Share the food and dessert instead of each ordering your own portion.”
Dr Chow suggested buying two-thirds of the food to prevent or reduce overeating. “Consider limiting dining out and engaging in food trends to certain days such as the weekends, and eating at home or more healthily on other days. Sprinkle in some exercises where possible.”

2. Your partner enjoys cooking and feeding you – and equates food with love
“Good communication is key, so that everyone is on the same page about losing weight,” said Chen. “Be clear and specific in your request about your needs and limits (for example, when the portion is too much), while maintaining the relationship by being kind and validating your partner’s love and efforts for you. You could also suggest alternative healthier food that your partner can cook that will support the weight loss,” she said.
Let your partner know that it’s the thought, not the amount of food, that lets you know of their affection, said Dr Chow. “For example, you could say to your partner that a small snack holds the same meaning to you as a whole meal.”
3. Your partner is not the active type
The key is motivation, said Assoc Prof Shabbir. “Avoid derogative remarks, negative comments and being judgemental. Co-create an environment for sustainable activity with your partner. Group activities with friends are also encouraged.”
And you don’t have to commit full-on to the activity either, said Chen. “It can be a gradual build-up of activity to get to the desired goal. There are many ways to lose weight and intense exercise is not the only way. Discuss with each other what might be new things to try together to get moving or leverage shared interest to increase the activity level.”
For example, simply running may sound boring, said Dr Chow. So how about rollerblading or skateboarding through scenic parks instead? “Taking romantic walks could also be a good un-exercise-like exercise.”

4. You’re both too tired to exercise or eat healthy after coming home from work
Things can feel overwhelming when we have many priorities to juggle, said Chen. To get around it, start small. Exercising and eating healthier all the time would be ideal, she said, but if it’s not realistic in the present moment, try breaking down expectations into manageable pieces and evaluate the feasibility of the plan.
If you can’t find time after work to exercise or cook healthy food, do it during work, said Assoc Prof Shabbir. “You could walk to take a bus rather than a taxi. Do not skip meals as you are likely to eat twice as much, or much more than the usual amount at your subsequent meal.”

5. You always end up ordering or cooking the same food
“Thinking of new things to eat or researching new recipes require effort, which is why many people put it off and go back to the same routine," said Chen. Be patient with yourself as change takes time, she added.
Try this: Do up a list of new foods or recipes, and make it your goal to try something new once a week or month. Schedule it on weekends or days when you’re not that busy instead of deciding new things to eat on the spot, said Chen. “Take it one step at a time to get both of you closer to where you want to be in your journey to lose weight as a couple.”
Or create a little spinning wheel, suggested Dr Chow, to help you pick a random food idea. Or ask others for their food recommendations, she said.