A new study has shown that obese youth are twice as likely to have overweight friends.
Lead author Dr Thomas Valente, professor of preventive medicine at the Keck School of Medicine insists that 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 behaviours that cause obesity.
"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," he added.
They 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," said Valente.
"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 behaviours which contribute to obesity are social in nature," he added.
The study appears in the Journal of Adolescent Health.