The persistence of and resistance to social norms regarding the appropriate amount to Eat: A preliminary investigation.

We conducted a preliminary investigation on the resistance to, and persistence of, social influence regarding the appropriate amount to eat, defined in terms of eating an amount similar to that eaten by a confederate. Participants ate pizza both alone and in the presence of remote confederates presenting either a high or low eating norm. In the portion of the experiment examining resistance to social influence, participants given an initial opportunity to form a personal eating norm by eating alone for one session in the absence of social influence were no more resistant to low eating norms than were those who had no such opportunity; however, those who ate alone for two or three prior sessions did show resistance. For the high eating norm, it took three eating alone sessions to create resistance. In the portion of the experiment examining persistence of social influence, when participants ate alone following a session with norm-setting remote confederates, the effect of the social influence persisted. However, the persistence effect varied by norm and weakened over time. Participants modeled a low eating norm for only one additional session and the size of the effect was markedly weaker. By contrast, the high norm persisted for all of the remaining sessions. Thus, individuals' social influence histories can affect their eating.

Are large portions responsible for the obesity epidemic?

Large portion sizes are frequently blamed for the obesity epidemic. In this paper, we examine the culpability of large portion sizes. It is true that portion sizes have increased during the obesity epidemic, but there is as yet little evidence that exposure to large portions produces significant weight gain. Furthermore, some evidence argues against the role of large portions in the obesity epidemic. For instance, the epidemic is largely a matter of weight gain among the upper half of the population weight distribution, whereas large portions appear to have an indiscriminate effect on food intake. Factors other than the size of individual meals may well be responsible for a great deal of the observed population weight gain.

Mechanisms underlying the portion-size effect.

The portion-size effect (PSE) refers to the fact that people eat more when served larger portions. This effect is neither obvious nor artifactual. We examine the prevailing explanations (or underlying mechanisms) that have been offered for the PSE. The dominant candidate mechanism is "appropriateness"; that is, people accept the portion that they are served as being of an appropriate size and eat accordingly. Because people do not necessarily finish the portion that they are served, variations on the basic appropriateness mechanism have been suggested. We also consider some evidence that is inconsistent with an appropriateness explanation, including the appearance of the PSE in children as young as two years of age. We also examine other mechanisms that do not rely on appropriateness norms. Visual food cues may assist in assessing appropriateness but may also drive food intake in a more mindless fashion. Larger portions induce larger bites, which may increase intake by reducing oral exposure time and sensory-specific satiety. We consider further research questions that could help to clarify the mechanisms underlying the PSE.

"She got more than me". Social comparison and the social context of eating.

Eating is a social activity for most people. Other people influence what and how much an individual chooses and eats. Such social influence on eating has long been recognized and studied, but we contend here that one important social influence factor, social comparison, has been largely overlooked by researchers. We review the literature on comparing oneself to others on eating and weight-related dimensions, which appears to have an effect not only on eating per se, but also on self-image, body dissatisfaction, and emotions. Social comparison processes may well underlie many of the social influence findings discussed in this special issue.

Comparing live and remote models in eating conformity research.

Research demonstrates that people conform to how much other people eat. This conformity occurs in the presence of other people (live model) and when people view information about how much food prior participants ate (remote models). The assumption in the literature has been that remote models produce a similar effect to live models, but this has never been tested. To investigate this issue, we randomly paired participants with a live or remote model and compared their eating to those who ate alone. We found that participants exposed to both types of model differed significantly from those in the control group, but there was no significant difference between the two modeling procedures.

The effects of degree of acquaintance, plate size, and sharing on food intake.

This study examined the effects of degree of acquaintance, plate size, and sharing on the amount of pasta individuals served themselves and subsequently consumed and whether or not they took second helpings. Fifty-seven pairs of female participants ate a meal of pasta; the members of each pair were either friends or strangers. During the meal, they served themselves either from a common serving bowl or from individual serving bowls and onto either small or large plates. The findings indicated that participants who ate with a friend served and consumed more than those who ate with a stranger, and those who shared served and consumed less than those who did not share. However, this sharing effect seemed to occur only when participants ate from small plates. Whether or not participants reported taking second helpings was influenced by all three of the independent variables.

Internal and external moderators of the effect of variety on food intake.

Many factors contribute to how much we eat. One such factor is the variety of different foods available. The current article reviews the variety literature with a specific focus on the factors that moderate the effects of variety on food intake and that moderate the processes that may underlie the variety effect (i.e., sensory-specific satiety and monotony). The moderators have been categorized as being of either an internal nature or an external nature. The literature suggests that internal moderators, including characteristics such as gender, weight, and dietary restraint, do not act as moderators of the variety effect. One possible exception to the absence of internal moderators is old age. Alternatively, external moderators, such as particular properties of food and the eater's perception of the situation, appear to affect the strength of the variety effect on intake to some degree. An evolutionary hypothesis may account for the distinct roles that internal and external variables play in moderating the variety effect. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

Competition affects food choice in women.

OBJECTIVE: To examine women's food choices after exposure to a threatening upward social comparison in an achievement situation. METHOD: Female university students performed three tasks in the presence of a confederate; for some, the situation was competitive and they were made to feel the confederate was likely to outperform them, whereas the remainder performed under noncompetitive circumstances. After completing the tasks, all participants chose a food to eat in a supposedly unrelated taste test. RESULTS: It was expected and found that participants in the high threat condition, in comparison with those in a low threat condition, would be highly motivated to restore their sense of self-worth by successfully competing in an area unrelated to the original inferiority and would, therefore, choose a lower calorie/more nutritious food. A secondary analysis revealed that it was primarily dieters whose food choices were affected by the threat. DISCUSSION: For dieters, competition by means of food choice can provide a means of restoring self-regard when self-esteem has been threatened in some other domain.

The relationship between restrained eating, pleasure associated with eating, and well-being re-visited.

Appleton and McGowan [Appleton, K. M. & McGowan, L. (2006). The relationship between restrained eating and poor psychological health is moderated by pleasure normally associated with eating. Eating Behaviors, 7, 342-347.] reported that pleasure associated with eating is an important moderator of the relationship between restrained eating and well-being. Using questionnaires, the current study re-visited this issue in order to determine the exact conformation of this interaction between pleasure and restraint and how it might predict well-being. A significant relationship was found between restraint and well-being--higher restraint scores were predictive of lower self-clarity, lower life satisfaction, and higher neuroticism. Furthermore, pleasure was an important moderator of this relationship for both self-clarity and neuroticism. Conditional slopes analyses revealed that individuals who were both high on pleasure associated with eating and high on restraint showed the lowest self-clarity and the highest neuroticism scores, while the opposite pattern was found for those high on pleasure but low on restraint. This study confirms that pleasure associated with eating is an important moderator of the relationship between restrained eating and well-being.

Wake up and smell the cookies. Effects of olfactory food-cue exposure in restrained and unrestrained eaters.

Few factors have been identified that bolster self-control processes and prevent overeating in restrained eaters; however, research on counteractive-control theory suggests that exposure to food cues may represent such a protective factor. To further investigate the effects of food-cue exposure, restrained and unrestrained eaters were randomly assigned to either a food-cue or no-cue condition, and their intake was measured. The results indicated that food-cue-exposed restrained eaters ate less than did non-exposed restrained eaters. The possible role of incidental food-cue exposure as a means for inhibiting intake in restrained eaters is explored.

Perceptions of undereaters: a matter of perspective?

We assume that people, to convey positive impressions of themselves, use the amounts eaten by others as limits beyond which their eating may be deemed excessive. One should, therefore, prefer eating partners who eat a lot because others' large intake renders one's own eating nonexcessive. Two studies were conducted to test this hypothesis. As predicted, participants liked confederates who ate more than they did better than those who ate less than they did, and they also rated their own intake as more appropriate when it had been exceeded by confederates than they did when it had been undercut by confederates. Noneating observers, instead, did not display a preference for eaters who ate more. Both noneating observers and active participants, however, rated eaters who ate less more positively than eaters who ate more on self-control-related items. We conclude that the nature of the behavior-impression association depends critically on the perspective of the rater.

Effects of food-cue exposure on dieting-related goals: a limitation to counteractive-control theory.

The present study investigated the effects of exposure to a food cue on the self-reported importance of dieting in those with low, medium, and high levels of dietary restraint. The results indicated that exposure to a food cue bolstered dieting-related goals in those who were low in dietary restraint but had no effect on the importance of dieting-related goals for those with medium or high levels of dietary restraint. The results demonstrate that exposure to temptations may differentially affect self-control processes depending on an individuals' level of dietary restraint.

Cognitive schemas: how can we use them to improve children's acceptance of diverse and unfamiliar foods?

Foods represent important stimuli for humans, especially for human children. After weaning, it is important that children quickly acquire knowledge about their food environment to avoid ingesting potentially dangerous substances. This paper discusses this process and its implications in terms of schemas. The effects of providing positive taste information to novel foods and of adding familiar flavors to novel foods are interpreted by means of the schema construct. A means of changing schemas through exposure to schema-inconsistent information is presented and evidence for its efficacy is described. Finally, the effect of early variety on subsequent willingness to eat unfamiliar foods is described and once again interpreted by means of the schema construct.

The role of familiarity on modeling of eating and food consumption in children.

This study investigates the effects of peer and sibling influence on the cookie intake of normal-weight children. A total of 44 children (24 girls and 20 boys) aged 5-11 participated in this study. Children played a sorting task while being exposed to a large amount of cookies. Children were tested alone or with an unfamiliar peer or with a sibling. Results indicated that the social condition was related to the participants' energy intake. Children eating with their siblings ate more cookies than did children eating with strangers and also consumed more cookies than did children eating alone. This pattern of results is consistent with previous research in adults indicating that familiarity between co-eaters influence how much one choose to eat. Furthermore, the degree of intake matching was extremely high among strangers, but low and not statistically significant in dyads of siblings. We conclude that matching effect is not ubiquitous and that familiarity affects the level of matching of eating in children.

Vulnerability to freshman weight gain as a function of dietary restraint and residence.

Although many studies have found that students gain weight during their first year at college, many others have not. Participants in the present study were classified according to their scores on the Herman/Polivy Restraint Scale and their place of residence-at home or on campus. Body weight was assessed early in the academic year and five months later. At the same sessions participants completed a questionnaire pertaining to their eating habits prior to beginning college (first session) and since coming to college (second session). Overall weight gain was 1.5 kg; those most likely to gain weight were restrained eaters living on campus, who gained an average of 4.1 kg. In addition, changes in eating habits were a significant independent predictor of weight gain.

Effects of social influence on eating in couples, friends and strangers.

Previous research indicates that both males and females eat less in the presence of a stranger of the opposite sex than in the presence of a same sex. Another literature shows that people tend to model or matching the amount eaten by others. The extent to which people are eager to inhibit their food consumption or match other's intake is likely to vary as a function of the characteristics of the co-eater. The present study examines how males and females adjust their level of eating as a function of their familiarity with and the gender of their eating companion, using a free-eating paradigm. Findings indicated that both the familiarity between co-eaters and the participants' gender predicted food consumption. Although unfamiliarity suppressed both men's and women's food intakes, the matching effect operated only when a female co-eater was involved. We conclude that the overarching motive (i.e., producing a positive impression) does not necessarily vary substantially across the various gender-familiarity combinations, but that the means or strategies (eating lightly and or matching of intake) by which the person accomplishes it and the strength of the motive vary as a function of the audience. In other words, in some social contexts self-enhancing motives can be served by restricting intake as well as through ingratiatory strategies such as attitudinal or behavioral conformity.

Influence of clear versus ambiguous normative information on food intake.

Two studies were conducted in order to examine the conditions under which social norms operate to control people's otherwise prepotent response to maximize eating. The social-normative model of eating assumes that people will follow one of two possible norms for "appropriate" eating behavior: the norm to eat minimally and the norm to avoid eating excessively. In Experiment 1, it was predicted that amounts eaten would be bimodally distributed (with the modes at or just below the two amounts chosen to represent minimal and excessive eating). Instead, most participants ate considerably more than either of the norms presented. Experiment 2 was intended to test the following explanation for these results: exposure to ambiguous norms liberated participants from normative constraints and led them to overeat. Experiment 2 demonstrated that exposure to clear norms in the same situation exerted a braking effect on overeating. We conclude that individuals are more likely to eat in accordance with their own desires when they cannot perceive that others are following a clear pattern of eating behavior and social norms are, therefore, not apparent.

Meal schemas during a preload decrease subsequent eating.

Two studies examined the effects of the induction of a meal schema on participants' behavior. In the first, participants ate identical preloads either in a traditional meal context or in a non-meal ("tasting session") context where the usual cues associated with meals, such as the use of dishes/utensils and being seated at a table, were present or absent, respectively. In a questionnaire assessing their impressions of the situation, participants in the meal condition gave evidence of the activation of a meal schema while the latter did not. That is, the former, in comparison with the latter, were more likely to spontaneously describe the situation using meal-related words, less likely to describe the situation using taste-related words, and rated the situation as feeling more like a meal. In the second study, participants eating the preload in an identical meal context, in comparison with those eating it in a non-meal context, ate less at a subsequent test meal. It was concluded that social cues in the form of Abstract knowledge about eating in one's culture may sometimes have a greater influence on food intake than physiological cues related to nutritional status.

Meal duration mediates the effect of "social facilitation" on eating in humans.

This experiment examined the 'time extension' explanation for the social facilitation effect, which is that people eat more as the number of co-eaters increases. Seventy male and 62 female participants ate a lunch consisting of pizza, cookies, and bottled water, alone or in (same-gender) groups of two or four and were given either 12 or 36 min in which to do so. The independent variables were gender, group size, and meal duration. The main dependent variable was amount consumed in the meal. The results showed that male participants ate more than did females, and participants eating the longer meal ate more than did those eating the shorter meal. However, the effect of group size was not significant. It was also the case that the amounts consumed by participants eating in two-person groups resembled one another to a greater extent than did of pairs of participants who ate alone or by participants in four-person groups. It was concluded that the results of the present paper provide strong support for the idea that the effect of group size on intake seen in previous studies is mediated by meal duration.

"Ugh! That's disgusting!": Identification of the characteristics of foods underlying rejections based on disgust.

Previous research has demonstrated that individuals' beliefs about the disgusting properties of foods play a central role in predicting willingness to eat novel foods of either animal or non-animal origin (Martins & Pliner, in press). The present study aimed to identify what characteristics of foods make individuals perceive them as disgusting. In this study, participants read a set of scenarios designed to depict potentially disgusting foods; participants in Sample 1 rated the perceived disgustingness of the foods while participants in Sample 2 rated the foods on a variety of attributes relevant to theoretical conceptions of disgust. Multidimensional scaling revealed two dimensions, aversive textural properties of the foods and reminders of livingness/animalness, that accounted for most of the variability in ratings of perceived disgustingness of the foods depicted in the scenarios. Implications for our current conceptualization of disgust are examined.