Married couples who are happy in their relationship are likely to face the danger of flesh pile-ups due to self contentment and rewarding relationship satisfaction.
Researchers in their months-long researches involved more than 160 newly-wed couples and found that the more contented a relationship is, the more the risk of weight they gained result of happiness.
Over four years, couples were regularly asked to rate their satisfaction with their marriage on a scale, while their weight and height were measured.
The study found that for each unit rise in satisfaction, on average, men and women gained one tenth of a BMI unit every six months — the equivalent of a pound a year for a woman who is 5ft 4 ins tall and weighs 8½ stone.
Researchers suggested that those who were happy with their partners might be less likely to worry about their figures, because they were not motivated to look elsewhere for love.
Dr Andrea Meltzer, of the Southern Methodist University, Dallas, said: “On average, spouses who were more satisfied with their marriage were less likely to consider leaving their marriage, and they gained more weight.
“In contrast, couples who were less satisfied in their relationship tended to gain less weight over time.”
The researchers based their findings on data from 169 couples.
Those who stayed together tended to put on weight, while divorce was associated with shedding the pounds.
“These findings suggest people perhaps are thinking about their weight in terms of appearance rather than health,” Dr Meltzer said.
The study, published in the Health Psychology journal, suggests young couples should be educated to think about their weight as a factor of maintaining their health.
Dr Meltzer said: “By focusing more on weight in terms of health as opposed to appearance, satisfied couples may be able to avoid potentially unhealthy weight gain.”
A different study in 2009 in the journal Obesity also showed that the risk of obesity rises the longer people live together.
Penny Gordon-Larsen, associate professor of nutrition at the University of North Carolina, listing some positive health benefits to marriage discovered that there was sharp decrease in cigarette smoking and lower mortality.
But she added: “We also see greater weight gain than in others of the same age, and greater risk of obesity.
“Maybe the cause of weight gain is not just age, but the pressure of shifting behaviours that result in weight gain.”
They were more likely to watch television together instead of going to the gym or playing a sport. Her research found that couples who lived together for more than two years – especially those who were married – were most likely to display similar obesity patterns and physical behaviors.
She added: “Maybe this a good time to intervene with these young couples and get them to have a more positive effect on each other.
“Couples can use that phenomenon to their advantage if they’re aware of what’s going on.” “They can be good influences on each other. That may be how they can avoid the extra pounds now associated with marriage.”