If you’re married or have been in a long-term relationship, someone over the years has probably half-joked about the weight gain they experienced in the first year or two (or ten). Some people chalk it up to routine, some say they eat (and snack) more, others stop going to the gym and cozy up to their comfortable routines.
Whatever the reason, researchers wanted to know if relationship weight gain was a real thing – and apparently it is. Over the last few years, there have been two studies in particular suggesting that, yes, the thing(s) you love most in life will lead to extra pounds and love handles to prove it!
Can Marital Satisfaction Predict Weight Gain?
Some believe it can, but others aren’t convinced. Earlier research seems to suggest that people who are satisfied in and with their relationships are generally healthier. In other words, happy wife, healthy life. Researchers call this the health regulation model.
But, in July 2013, researchers from Southern Methodist University in Dallas joined 169 newlywed couples on their marital journeys for four years and found something quite the opposite. Over the course of the study, spouses shared information eight times about their: 
Steps toward divorce
In contrast to the health regulation model, something called the mating market model turned out to be truer of the couples’ weight gain. This model suggests that people who are less happy with their relationship are more likely to try to lose weight. Researchers say this is because they have a desire to attract a (new) mate.  Therefore, spouses that are satisfied with their relationship are actually less likely to watch their weight because they are aren’t looking to leave their partner – they’re happy and comfortable with how things have gone so far in their marriage.
“Satisfaction is positively associated with weight gain,” says lead researcher, Andrea Meltzer.  “Spouses who are more satisfied tend to gain more weight, and spouses who are less satisfied tend to gain less weight.”
At the beginning of the study, husbands had a slightly overweight body-mass index (BMI) of 26 and wives had a healthy BMI of 23.
“For each unit of increase in satisfaction found, either by the person or the partner, a 0.12 increase in BMI occurred every six months, on average,” said Meltzer. 
Happy in Marriage, Heavier on the Scale