Peer influence on youth's snack purchases: a laboratory analog of convenience store shopping.

OBJECTIVE: This paper reports the results of two experiments using a laboratory analog to examine the influence of taxes and subsidies on youth's snack food purchases when alone (Experiment 1) and when in the presence of a same-gender peer (Experiment 2). METHOD: Adolescents (12-14-years-old) completed a purchasing task, during which prices of snack foods were manipulated, either alone in Experiment 1 (N=37) or in the presence of an unfamiliar peer in Experiment 2 (N=52). RESULTS: In both experiments, purchases of unhealthy snacks decreased and purchases of healthy snacks increased when the price of unhealthy snacks were taxed (increased). In Experiment 1 (alone), participants did not purchase more healthy snacks when the price of these snacks were subsidized (decreased). However, in Experiment 2 (when participants were in the presence of a peer), participants purchased more healthy snacks when these snacks were subsidized. CONCLUSION: Taxes and subsidies affect adolescents' snack purchasing, as does the presence of peers. The results of this study highlight factors that influence healthy and unhealthy snack purchasing behavior in young adolescents.

Effects of ostracism and social connection-related activities on adolescents' motivation to eat and energy intake.

OBJECTIVE: Assess the effect of ostracism and social connection-related activities on adolescents' motivation to eat and their energy intake. METHODS: Participants (n = 103; M age = 13.6 years) were either ostracized or included when playing a computer game, Cyberball. Next, they wrote about their friend (social-connection), watched television (distraction), or completed Sudoku puzzles (cognitive-load), and then completed a task to earn points toward snack food and/or socializing. Afterwards, participants were given access to food and social activities. RESULTS: Ostracized adolescents were more motivated to earn food than adolescents who were in the included/control condition. Follow-up contrasts indicated that ostracized adolescents who wrote about friends worked more for food points and consumed more food than other adolescents. CONCLUSION: Results suggest that social connection-related activities following ostracism may further deplete self-regulatory resources, thereby resulting in increased unhealthy food patterns. Study limitations as well as clinical implications of these findings are discussed.

Influence of parents and friends on children's and adolescents' food intake and food selection.

BACKGROUND: The influence of parents versus friends on youths' eating behavior has not been directly compared, and little is known about the developmental effects of social influences on their eating behavior. OBJECTIVE: The objective was to compare the effects of mothers and friends on children's and adolescents' energy intake from sandwiches and from healthy and unhealthy snacks and dessert foods. DESIGN: Twenty-three children (ages 5-7 y) and 27 adolescents (ages 13-15 y) ate a meal with their mother on one occasion and with a same-sex friend on another occasion. RESULTS: Male and female children consumed less energy from unhealthy snacks when in the presence of their mothers than when in the company of their friends. Conversely, female adolescents consumed less energy from unhealthy snacks and more energy from healthy snacks when they were with their friends than when with their mothers. CONCLUSIONS: Food selection is differentially influenced by the source of social influence and the age and sex of the child. Parents may act as an inhibitory influence on unhealthy eating for younger children. Adolescent girls may try to convey a good impression of healthy eating when eating with same-sex friends, but the eating habits of teenage boys are not as influenced by the social context. This trial is registered at clinicaltrials.gov as NCT00875576.

Impact of simulated ostracism on overweight and normal-weight youths' motivation to eat and food intake.

There is growing evidence that the experience of being ostracized can impair individuals' abilities to self-regulate, which in turn, leads to negative health behaviors, such as increased unhealthy eating. Research has focused on adults, but deficits in eating regulation in response to ostracism may be particularly detrimental for overweight or obese youth. This study examines the effects of a brief episode of ostracism on the motivation to eat and food intake of overweight and normal-weight young adolescents (M age=13.6 years). A computerized ball-tossing game (Cyberball) was used to induce ostracism or inclusion. Following the inclusion/ostracism manipulation, all participants completed an operant computer task to earn points exchangeable for portions of food or for time socializing with an unfamiliar peer. Participants' responses for food and their subsequent energy intake were recorded. As hypothesized, ostracized overweight participants responded more for food and had a greater energy intake than overweight participants in the inclusion/control condition; whereas this was not the case for normal-weight participants. These results are important as studies indicate that overweight and obese youth may be at risk of social isolation and peer difficulties. Social adversity, if left unchanged, may increase the difficulty of promoting long-term changes in overweight youths' health behaviors.

Do social activities substitute for food in youth?

BACKGROUND: Behavioral economics offers a framework to understand choice among alternatives. There is no research on the interrelationship between food and social activity in overweight and non-overweight children. PURPOSE: The purpose of this study is to test the substitutability of food and social interactions using behavioral economic methods in overweight and non-overweight youth. METHODS: Fifty-four (24 males and 30 females) overweight and non-overweight youth aged 9 to 11 years old were tested using a behavioral choice paradigm which involved participants responding to earn points exchangeable for food and/or social activity. RESULTS: Youth substituted food for social activities when the cost of social time with an unfamiliar peer increased (p < 0.05) and substituted food for social activities with an unfamiliar peer when the cost of food increased (p < 0.05). However, when interacting with a friend was the alternative, participants did not substitute food for social interactions. CONCLUSIONS: Social interactions can serve as a substitute for food in both lean and overweight youth.