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'Friending' Your Way Thin

Dieters who make more connections in online weight-loss communities lose more weight

• First study to explore the power of online social networks in the battle of the bulge

• Dieters who engaged the most lost more than 8 percent of body weight in six months

• Scientists used data from’s online weight-loss community

• “I was very surprised by how … social connectedness translated into greater weight loss,” researcher says

EVANSTON, Ill. --- If you want to lose pounds using an online weight management program, don’t be a wallflower. A new Northwestern University study shows that online dieters with high social embeddedness -- who logged in regularly, recorded their weigh-ins and ‘friended’ other members -- lost more than 8 percent of their body weight in six months.

The less users interacted in the community, the less weight they lost, the study found.

“Our findings suggest that people can do very well at losing weight with minimal professional help when they become centrally connected to others on the same weight loss journey,” said Bonnie Spring, an author of the study and professor in preventive medicine at Northwestern University Feinberg School of Medicine.

The study, published Jan. 28 in the Royal Society journal Interface, is the first to use data from an online weight management program to investigate social network variables and reveal which aspects of online social connectedness most strongly promote weight loss.

The scientists found that users who did not connect with others lost about 5 percent of their body weight over six months, those with a few friends (two to nine) lost almost 7 percent and those with more than ten friends lost more than 8 percent.

“There is an almost Facebook-like social network system in this program where people can friend each other and build cliques,” said Luís A. Nunes Amaral, senior author of the study. “In this case, we found the larger your clique, the better your outcomes.”

Amaral is a professor of chemical and biological engineering in the McCormick School of Engineering and Applied Science and a leading researcher in the areas of big data and complex systems. His also is co-director of the Northwestern Institute on Complex Systems (NICO).

Spring, who also is the director at the Center for Behavior and Health in the Institute for Public Health and Medicine at Feinberg, and Amaral met through a common interest in the science of teamwork and collaborated on this research.

Spring had access to a large dataset from’s online weight-loss community. Users of CalorieKing’s program pay a membership fee for access to weight-loss tools and an online community. Amaral’s lab had the expertise to analyze user data and uncover trends in this complex network.

The data provided did not include the identities of users, but it provided their sign-up date, age, height, gender and initial weight and time-stamped activities within the online community for nearly a year. Engagement, such as recorded weigh-ins, friendship requests and online communication, was analyzed. The scientists didn’t have access to any of the text that was exchanged between users.

“We found that the frequency with which you report your weight is a good indictor of positive outcomes,” Amaral said. “If you monitor your weight, you are engaged.f you communicate online with other people you are even more engaged, and when you need support you might be able to get it. There are some nice characteristics about this social network.”

The gold standard for weight loss is intensive lifestyle treatment involving a minimum of 16 60-to-90 minute individual or group treatment sessions covering diet, physical activity,and behavior change, Spring said. Those who regularly track their progress, known as self-monitoring, lose more weight in clinical studies.

This study found that self-monitoring was associated with greater weight loss, too, but Spring was surprised that even greater weight loss was associated with being highly embedded in a network of other people trying to lose weight.

“In the clinic, we don’t have the ability to connect people with such a large network of others on the same journey to lose weight,” Spring said. “I was very surprised by how lawfully each step-up in social connectedness translated into greater weight loss. We could clearly see the benefit of the online social network for weight-loss success.”

For those lacking time or geographic proximity to attend in-person weight loss treatment, an online weight loss program seems to be a good alternative, Spring said, particularly if you take advantage of the self-monitoring and social networking features.

Amaral said this online social support community approach could work in other areas of behavioral medicine -- such as depression and alcoholism -- where in-person meetings are recommended.

“Modern life is so complex and stressful, to go somewhere for a meeting is often not practical,” Amaral said. “It is hopeful that this alternative approach, of going online for support, could work.”

The National Institutes of Health (grants R01HL075451, RC1DK087126 and 3UL1RR025741–02S4) supported this research.

Other authors include Julia Poncela-Casasnovas from Universitat Rovira i Virgili in Spain, Arlen C. Moller of the Illinois Institute of Technology and Daniel McClary, Rufaro Mukogo, Christine A. Pellegrini, Michael J. Coons, Miriam Davidson and Satyam Mukherjee of Northwestern University.