Obesity is a disorder of positive energy balance, with energy intake exceeding energy expenditure. Food is a powerful reinforcer in youth and one of the factors that may relate to the positive energy balance in obese youth is differences in the motivation to eat [1
]. A number of studies on choice responding and preference have examined factors that influence the choice between eating and engaging in alternative activities [2
]. However, most of this research isolates the individual from any possible source of social influence and few experimental studies have directly tested whether the social context influences the food intake of children and adolescents.
Studies in adults indicate that individuals often eat more and spend more time eating when in the presence of others than when alone (e.g., [3
] see also [5
]), a phenomenon known as social facilitation of eating. However, there is also evidence that the presence of others may impact differently on the eating behavior of overweight and normal-weight individuals. For instance, Krantz reported that overweight individuals chose higher-caloric meals in a cafeteria when they were alone than when in the presence of others [6
]. In contrast, normal-weight individuals chose larger meals when with others than when alone, which is consistent with the literature on social facilitation of eating [7
]. Krantz suggests that the social stigma associated with overweight and obesity accounts for these results, postulating that heightened concerns about weight led to reduced intake in obese individuals in the presence of others. By contrast, normal-weight individuals presumably increase their intake when in a group as a result of the social nature of the upcoming lunch — rather than eating on the run, the lunch becomes a social opportunity [6
]. This logic follows the ‘time extension’ hypothesis put forth by De Castro [3
] (see also [5
]). Therefore, it appears that within adults, weight status is an important factor influencing the effects of the presence of others on food intake and eating behavior.
Herman et al. [8
] developed a normative framework of the effects of others on food intake. This model can account for differences between overweight and normal-weight children in response to the social context. At its most basic level, the model posits that palatable food motivates eating, while the presence of others operates to determine when eating stops. That is, when eating with others, and in absence of clear guidelines, people use the behavior of others as an indication of “appropriate” eating. The amount that is appropriate to eat will depend on the social context (i.e., how much others are eating) and situations differ in the extent to which they increase or inhibit food intake. Presumably, people use the amount eaten by others to regulate their own intake to avoid incurring the stigma of excessive eating [9
] and also because they believe that doing so will lead others to like and accept them (see [10
] for an analysis of normative conformity).
Individuals’ concerns with eating too much in front of others do not seem misguided. A well-substantiated literature indicates that negative stereotypes apply to those who eat excessively [11
]. Research shows that a set of negative personality traits is attributed to people who are overweight and those who eat large amounts. It is also widely assumed that people become overweight because of a lack of self-control around food [12
]. Overweight people are stereotyped as lazy, self-indulgent, unattractive, lacking self-esteem, socially inept, uncooperative, and intellectually slow [14
]. Similarly, peer sociometric assessments consistently show that overweight children are perceived more negatively than are normal-weight youths. Children are less inclined to seek the company of overweight peers, and they do not enjoy interacting with them as much as they do with lean kids [19
]. Rejected children often respond to victimization by disengaging from the social environment as a way of avoiding further prejudice [21
]. Avoidance of social activities may not only deny children the opportunity to incorporate alternative leisure activities and recreations as part of a healthy lifestyle, but may also increase their involvement in obesigenic activities such as television watching and snacking [23
A corollary of weight stigmatization is that overweight individuals may attempt to decrease their food intake in front of others to avoid incurring the stigmas related to overweight individuals who eat excessively. In fact, de Luca and Spigelman [24
] found that obese college students ate close to nothing in the presence of a lean confederate, but consumed a large amount in company of an obese experimental confederate. Normal-weight participants’ intake was unaffected by the confederate’s weight. De Luca and Spigelman suggested that obese participants ate less in the presence of a normal-weight confederate due to self-consciousness and ate more with an overweight participant due to solidarity. The self-consciousness interpretation is similar to Maykovich’s contention that overweight individuals suppress their intake in front of others in order to counteract the attribution that their excessive weight is due to excessive eating [10
]. In sum, it appears as though social influences may operate differently in overweight and lean individuals as a result of differences in social stigma, and potential concern in overweight (but not normal-weight) individuals about impressing other non-overweight individuals.
There has not yet been any systematic experimental study of the effects of social context on the food intake of overweight and normal-weight children. This is surprising as research shows that negative social interactions may be among the most detrimental experiences on unhealthy eating habits in youth [25
] and that overweight youth are significantly more likely than their non-overweight peers to report binge eating [26
]. In this respect, it is useful here to remember that pathological eating is more likely to occur when eaters are alone than when they are with others [32
] and the introduction of another person into the eating situation is likely to stop the binge in its tracks [33
The present study examines how the social context (i.e., alone versus presence of peers) influences overweight and normal-weight children’s food intake and their time allocation to eating area and a play area. Given the evidence that stigmatization of overweight exists in children as well as adults; we expect differences in the eating behavior of overweight and normal-weight children. Some limited research in adults (i.e., [6
]) has supported that this differentiation occurs; however, this research was observational and it assessed meal choice rather than actual food intake. In the present study, we expected that the presence of others would suppress the intake of overweight children, but facilitate the food consumption of normal-weight children. The free-eating paradigm used in the current study also allowed for testing of whether overweight and normal-weight children spend a differential amount of time playing versus eating depending on the social context. Consistent with the predictions for food intake, it was predicted that overweight children would spend more time in the eating area when alone than when with others, while normal-weight children were expected to spend more time in the eating area in the presence of others than when alone.