Tricia Leahey Ph.D. Finds Ripple Effect with Weight Loss

Pick your friends well, and find a group with whom to lose weight. These are the findings of researchers from The Miriam Hospital’s Weight Control and Diabetes Research Center and The Warren Alpert Medical School of Brown University.  In their recent study with lead author Tricia Leahey Ph.D. of The Miriam and Alpert Medical School, they found that shedding pounds can have a ripple effect.

Published in the online journal Obesity, the study showed that, just as obesity can be socially influenced, so too can weight loss.  As Dr. Leahey said,

“We know that obesity can be socially contagious, but now we know that social networks play a significant role in weight loss as well, particularly team-based weight loss competitions. In our study, weight loss clearly clustered within teams, which suggests that teammates influenced each other, perhaps by providing accountability, setting expectations of weight loss, and providing encouragement and support.”

Today, there are many group-based weight loss programs from Weight Watchers to the television show The Biggest Loser.  The question that Leahey's team examined was if having weight-loss teammates and social influence actually makes a difference for an individual's weight loss.

The findings for their research came from a 2009 Shape Up Rhode Island (SURI) campaign that included a 12 week statewide online weight loss competition. It was designed by the study co-author Arjiv Kumar, M.D.  It included 3330 overweight and obese people with 987 teams that averaged between 5 and 11 people each.  There were three parts to the competition including weight loss, pedometer steps and physical activity.

As Leahey explained,

“This is the first study to show that in these team-based campaigns, who’s on your team really matters. Being surrounded by others with similar health goals all working to achieve the same thing may have really helped people with their weight loss efforts.”

She added, “We’re all influenced by the people around us, so if we can harness this positive peer pressure and these positive social influences, we can create a social environment to help encourage additional weight loss.”

Additional co-authors of the study with Leahey included: Rena R. Wing, Ph.D., director of The Miriam Hospital’s Weight Control and Diabetes Research Center and professor of psychiatry and human behavior at Alpert Medical School; and Brad M. Weinberg, M.D. and Rajiv Kumar, M.D. co-founders of ShapeUp, Inc.