The Boston Globe reports on a series of new studies which draw upon mapping social networks and behavioral economics to help us better understand those new year’s resolutions to lose weight. These studies suggest that a spouse’s weight loss success can rub off on the other.

The study from the University of Connecticut says that couples not only tend to gain weight together, they can also lose it as a pair, even if only one of them is enrolled in a formal program. The spouses of the patients who attended regular meetings to encourage making dietary changes lost about five pounds over the course of a year, according to the results of the large clinical trial that examined weight loss strategies for people with type 2 diabetes.

“It was impressive, given they were not involved in the study program,” Amy A. Gorin, assistant professor of psychology at UConn and lead author of the article published in the International Journal of Obesity, said in an interview. “Intervening with one person in a family has a larger impact than we realized before.”

This new study draws upon the work of sociologist Nicholas Christakis…

Harvard sociologist and internist Dr. Nicholas Christakis made waves with a study last year linking obesity to social networks. Gorin, who cites his work in her paper, finds the power of peer influence encouraging when it’s flipped to the positive side.

Among the 357 couples she tracked, many of their food choices in the home became healthier – fewer potato chips and more fruits and vegetables, for example. Physical activity picked up, too.

“For some people, it was motivating to see someone start to exercise and eat healthier food,” she said, citing anecdotal evidence.

“I think my message would be, don’t underestimate the power of the environment on you,” she said. “If you start your New Year’s resolution with ‘I’m going to have enough willpower this time,’ I think you set yourself up for failure if you don’t have the support of the environment around you.”

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