Parents are acutely aware of the influence of friends on their children's behavior -- how they dress, how they wear their hair, whether they drink or smoke.
A new laboratory-based study has shown that friends also may influence how much adolescents eat.
"Consider a person who usually comes home alone after school and eats out of boredom," says Sarah-Jeanne Salvy, PhD, assistant professor of pediatrics in the University at Buffalo's Division of Behavioral Medicine and first author on the study.
"But on this day, she has a play date with a friend and socializes instead of eating. In this case, socializing is acting as a substitute for eating. Identifying substitutes provides a potential way to reduce behavior.
"Our findings underscore the importance of considering the child's social network in studying youth's motivation to eat," says Salvy, a member of the Department of Pediatrics in UB's School of Medicine and Biomedical Sciences.
"Previous attempts to find substitutes for food and eating have not been very successful. To our knowledge, no research has studied whether social interactions can be a substitute for food in children."
The study appears online in the current issue of Annals of Behavioral Medicine.
The study involved 54 overweight and non-overweight youth -- 24 boys and 30 girls -- between the ages of 9 and 11. Each was assigned randomly to bring a friend or to be paired with an unfamiliar peer.
Study participants worked on a computer game to earn points exchangeable for food or time to spend with their friend or with an unfamiliar peer.
"The task got increasingly harder and the food and social points became more difficult to earn as a way to measure how hard youth were willing to work for food or for play time with their friend or with an unfamiliar peer," Salvy notes.
In the study, participants matched with an unfamiliar peer showed that when working for food became difficult, they switched to earn time with the unfamiliar peer, and when working for peer activity became harder, they switched to earn food.
However, participants assigned to the friend condition continued to work for time with their friends instead of working for food.
"Peer rejection and ostracism are obvious costs imposed on social interactions," says Salvy. "Even the unavailability of one's peers or friends can limit youth's access to social settings and situations. As a result, children may choose to engage in eating and sedentary activities when social alternatives are unavailable.
"There is emerging evidence that a youth's social network may be uniquely relevant and influential to eating behavior and choice of activities," she continues. "Individuals are influenced by the eating and activity norms set by those around them, and the results of the present study suggest that friendship can provide an alternative to eating.
"These findings, and the work of others, imply that decreasing sedentary behavior and increasing active leisure activities may require meaningful relationships with friends, as friendship may help to promote or 'socialize' active lifestyles."
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