USC study finds links between obesity and adolescents' social networks

Researchers from the Institute of Prevention Research at the Keck School of Medicine of the University of Southern California (USC) found in a recent study that overweight youth were twice as likely to have overweight friends.

"Although this link between obesity and social networks was expected, it was surprising how strong the peer effect is and how early in life it starts," says lead author Thomas Valente, Ph.D., professor of preventive medicine at the Keck School of Medicine.

The study appears in the August issue of the Journal of Adolescent Health, available online July 20 at http://journals.elsevierhealth.com/periodicals/jah/home.

Previous data had shown a connection between overweight adults and their social peers. However, the USC study used more advanced statistical modeling techniques than previous research and the association remained strong, Valente says.

"The findings certainly raise health concerns because when kids start associating only with others who have a similar weight status it can reinforce the negative behaviors that cause obesity," he says.

In-school surveys were conducted among 617 students ages 11-13 from the greater Los Angeles area. In addition to finding that overweight adolescents were more likely to have overweight friends than their normal-weight peers, the researchers also found that overweight girls were more likely to name more friends, but less likely to be named as a friend than normal-weight girls.

"Researchers tend to focus mainly on health consequences when talking about weight with adolescents," Valente says. "But we also need to be sensitive to the reality that there can be a social cost for overweight youth as well."

Interventions should take these peer constructs into account, he says. For parents and educators, this may mean being conscious of potential social consequences that children may suffer as a result of being overweight; and acknowledge that many of the behaviors which contribute to obesity are social in nature."

He pointed out that more longitudinal studies are needed for further recommendations on the relationship between being overweight and social status among adolescents.