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Pre-exposure to food cues has often been shown to increase food intake, especially in restrained eaters. This study investigated the role of expectations in the effect of such pre-exposure on food intake. A sample of 88 undergraduate women was exposed to visual food cues (photos of grapes and chocolate-chip cookies). In a 2 × 2 × 2 design, participants were explicitly told to expect that they would be tasting and rating either grapes or chocolate-chip cookies. Participants subsequently completed an ostensible taste test, in which they tasted and rated either grapes or cookies, such that half were given the food that they had been led to expect and the other half were given the other food. Participants' restraint status (restrained versus unrestrained) was based on their scores on the Revised Restraint Scale (Herman & Polivy, 1980). A significant interaction between expected food and restraint status was found. When participants were led to expect that they would be tasting grapes, restrained and unrestrained eaters did not differ in their subsequent consumption (of either grapes or cookies). However, when participants were led to expect that they would be tasting cookies, restrained eaters ate significantly less (of both grapes and cookies) than did unrestrained eaters, even though craving ratings were similarly elevated for both restrained and unrestrained eaters. The findings are consistent with counteractive control theory in that restrained eaters who expected to eat a high caloric food may have been able to activate their dieting goal, thereby limiting their food intake. The findings further point to an important role for expectations in the understanding and regulation of food intake in restrained eaters. [ABSTRACT FROM AUTHOR]

The social facilitation of eating (i.e., people eating more in groups than when alone) has been studied for about three decades now. In this paper, we review the empirical research (diary studies, observational studies, and experimental studies) of social facilitation, attending to factors that increase or decrease socially facilitated eating. We also review the various explanations (e.g., “time extension”) that have been offered for the effect and offer our own speculations as to the underlying mechanisms. Further, we discuss promising directions for future research on the social facilitation of eating. [ABSTRACT FROM AUTHOR]

Highlights: [•] Does dietary restraint suppress or promote future weight gain? [•] A prospective study (3-year follow-up) in a representative Dutch sample. [•] Body mass change, Dietary restraint, Concern for Dieting and Weight Fluctuation. [•] Higher dietary restraint longitudinally predicted increases in BMI in females. [Copyright &y& Elsevier]

Abstract: Earlier studies assessing the possible moderator effect of self-reported emotional eating on the relation between stress and actual food intake have obtained mixed results. The null findings in some of these studies might be attributed to misclassification of participants due to the use of the median splits and/or insufficient participants with extreme scores. The objective of the two current studies was to test whether it is possible to predict distress-induced eating with a self-report emotional eating scale by using extreme scorers. In study 1 (n =45) we used a between-subjects design and emotional eating was assessed after food intake during a negative or a neutral mood (induced by a movie). In study 2 (n =47) we used a within-subjects design and emotional eating was assessed well before food intake, which occurred after a control or stress task (Trier Social Stress Task). The main outcome measure was actual food intake. In both studies self-reported emotional eating significantly moderated the relation between distress and food intake. As expected, low emotional eaters ate less during the sad movie or after stress than during the neutral movie or after the control task, whereas high emotional eaters ate more. No such moderator effect was found for emotional eating in the entire sample (n =124) of study 1 using the median-split procedure or the full range of emotional eating scores. We conclude that it is possible to predict distress-induced food intake using self-reports of emotional eating provided that the participants have sufficiently extreme emotional eating scores. [Copyright &y& Elsevier]

Abstract: Manipulated perceptions of the portion size of food influence subsequent eating by restrained and unrestrained eaters. In the present study, all participants were served a same-sized slice of pizza. For one-third of participants, their slice appeared larger than the slice being served to another ostensible participant, another third perceived their slice as smaller, and the final third did not see a second slice. All participants then proceeded to “taste and rate” cookies in an ad lib eating opportunity. A significant interaction reflected the fact that when the pizza slice was perceived as large, restrained eaters tended to eat more cookies whereas unrestrained eaters tended to eat less cookies. Emotion data suggest that the differential responses of restrained and unrestrained eaters to the belief that they have overeaten relative to another eater influenced their subsequent dissimilar ad lib eating behavior. [ABSTRACT FROM AUTHOR]

Abstract: This study examined whether young men adjusted their snack-food intake to that of a same-sex eating companion. Additionally, hunger was assessed as a possible moderating variable. A total of 59 young men (M age=21.73) participated. An interaction between participants’ hunger and confederate''s intake on the total amount of snack food (in grams) consumed was found. Only those males who were hungry at the start of the experiment modeled the intake of their eating companion. This finding suggests that hunger may play an important role in explaining the magnitude of social modeling among young men. [Copyright &y& Elsevier]

Abstract: This study examined which individuals in particular are susceptible or resistant to develop overweight in our current obesogenic environment. A cross-sectional study was conducted in a sample of 1342 people representative of the general population in the Netherlands. Overweight-level (normal body weight≥17.5 BMI [weight in kilograms/height in meters squared, as self-reported] <25) versus overweight ((BMI≥25)) and overeating, as measured by questionnaire, were assessed in relation to dietary restraint, emotional eating and external eating, as assessed with the Dutch Eating Behaviour Questionnaire. Both dietary restraint and emotional eating moderated the relationship between overconsumption and overweight, but that there was no (positive) main effect or moderator effect for external eating. It was concluded that dietary restraint may prevent people who overeat from getting overweight. An individual''s final level of body weight may possibly be determined more by people''s tendency toward emotional eating than by people''s sensitivity to environmental food cues. [Copyright &y& Elsevier]

Abstract: Consumption stereotypes refer to judgments about others based on their food intake. We review the empirical research on stereotypes based on what and how much people eat. The characteristics stereotypically associated with food intake pertain to domains ranging from gender roles and social appeal to health and weight. For example, people who eat “healthy” foods and smaller meals are seen as more feminine; conversely, those who eat “unhealthy” foods and larger meals are seen as more masculine. We further discuss how these stereotypes can be exploited by the eater to convey a particular impression (e.g., femininity, social appeal). Finally, we discuss the ways in which using food intake as an impression-management tactic can lead to chronic food restriction and unhealthy eating habits. [Copyright &y& Elsevier]

Abstract: We examine the principal features of dieting using an evolutionary perspective, which sheds light on certain anomalies while raising other interesting questions. We focus on (a) the reasons that dieters give for dieting, (b) the difficulty of dieting, and (c) the apparent opposition between the proclivities toward self-indulgence and self-control. We propose that while self-indulgence and self-control both serve adaptive functions, these evolved tendencies are naturally triggered by different ecological challenges. Implications for dieting in an ecology of plenty are explored. [Copyright &y& Elsevier]

Restrained and unrestrained eaters were exposed to fictitious hunger reports (high-hunger, low-hunger) of ostensible prior participants in the experiment. In the control condition, participants were not exposed to prior-participant reports. Participants rated their own hunger and then consumed cookies during a ‘taste-test.’ The fictitious hunger ratings of prior participants exerted a strong effect (p<0.001) on actual participants'' hunger ratings; however, food intake was not affected by the fictitious hunger ratings (or by the actual participants'' hunger ratings). We discuss the disjunction between hunger ratings and eating, specifically whether (a) hunger reports were fabricated in response to social pressure or (b) eating is controlled by factors other than hunger. [Copyright &y& Elsevier]

Defining and measuring such qualities as restrained eating or dieting may require more than simply administering questionnaires and assuming that we are identifying the population that we wish to study. Different questionnaires may identify different types of restrained eaters, and even deciding what restrained eating consists of is a complicated endeavor. We discuss how to define and measure restrained eating, specifying key attributes, and acknowledging the problems inherent in relying on self-report instruments. We conclude that given the difficulties in defining such constructs as restrained eating, we need to specify more clearly exactly what our research questions are, in order to be sure that we are identifying the populations with the attributes necessary to answer those questions. [ABSTRACT FROM AUTHOR]

The Theory of Normal Eating suggests that how much others eat sets an upper limit for how much it is appropriate to eat. This study tested the hypothesis that restrained eaters, who typically eat less than they want to, would be more responsive to a high-intake norm than would unrestrained eaters. Data were combined from 8 experimental studies (total N = 735 female participants; 305 restrained eaters, 430 unrestrained eaters). Each study: (a) included a low-intake norm, a high-intake norm, and a no-norm control condition; (b) measured participants' food intake; and (c) included the Restraint Scale as a measure of dietary restraint. There were no differences between restrained unrestrained eaters in the no-norm control condition or in the magnitude of the inhibition effect (i.e., the difference between the low-intake norm condition and the control condition). There was, however, a restraint difference in the magnitude of the augmentation effect (i.e., the difference between the high-intake norm condition and the control condition). Restrained eaters showed a larger augmentation effect (d = 0.58; 95% CI = 0.29, 0.87) than did unrestrained eaters (d = 0.20; 95% CI = -0.05, 0.45). Social norms provide an upper limit for acceptable food intake, with high-intake norms permitting (but not requiring) individuals to indulge themselves. The fact that restrained eaters were more responsive to the high-intake norm than were unrestrained eaters suggests that the high-intake norm gives restrained eaters permission to indulge when they typically eat less than they want to. [ABSTRACT FROM AUTHOR]

Abstract: Dyads composed of unacquainted females watched a video while snacking on pizza. Their extraversion and self-monitoring scores were used to predict the extent to which individuals within dyads matched each other''s food intake. Matching of intake was high irrespective of the personality composition of the dyad. We consider elements of the situation that enhanced matching and whether personality might moderate matching effects. [Copyright &y& Elsevier]

People often fail to acknowledge external influences on their food intake, but there might be some circumstances in which people are willing to report that those external factors influenced their behavior. This study examined whether participants who believed that they had overeaten would indicate that the portion size they were served influenced their food intake. Participants (119 women) ate a pasta lunch at two separate sessions, one week apart. At the second session, participants were randomly assigned to receive either a regular portion of pasta (the same portion as the first session) or a large portion of pasta (a portion that was twice the size), and to receive false feedback about their food intake indicating that they had either eaten about the same as or substantially more than they had at the previous session. Participants were then asked to indicate the extent to which the amount of food served influenced how much they ate at that second session. Compared to participants who were informed that they had eaten the same amount across the two sessions, those who were informed that they ate more at the second session reported a stronger influence of the amount of food served if they also received a large portion of pasta, but not if they received a regular portion of pasta. These findings suggest that the willingness to implicate external influences (e.g., portion size) on one's food intake may be driven by a self-serving bias, providing an "excuse" for overeating. However, the external cue must be salient enough to be a plausible explanation for one's behavior. [ABSTRACT FROM AUTHOR]

Social modeling is a powerful influence on people's food intake: When there is a clear and consistent norm, people eat more when eating with someone who eats a lot and eat less when eating with someone who eats only a little. In three studies, the present research examined how clear versus ambiguous social-normative information influences the modeling of food-related decisions. Using a novel online decision-making paradigm, female participants (total N = 1042) were provided with information about how many cookies previous participants had supposedly selected (no information was provided in the control condition), and then decided how many cookies they would choose for a snack. When there was a clear and consistent norm, the typical social modeling effect was observed. When there was a small number of "dissenters" whose responses conflicted with the norm set by the majority, participants' cookie selection still conformed to the behaviour of the majority (Studies 1 and 2). It was only when the behaviour of the previous participants was highly ambiguous that participants behaved as if they had been given no normative information (Study 3). By demonstrating that, except in extreme cases, people use the available information to discern a social norm that influences their behaviour, these findings highlight the power of social norms related to food-related decisions. [ABSTRACT FROM AUTHOR]

Abstract: We examined whether a same-sex peer''s vegetable consumption would predict the number of vegetable pieces eaten by the participant. A total of 116 Dutch women (M age=20.28; M BMI=21.68) participated. Their nutrient-dense food intake was measured during a 15-min break between two tasks, consisting of rating television advertisements. Participants consumed more vegetables when exposed to a peer eating a large number of vegetables than when exposed to a peer eating a small number or nothing. These findings suggest that social modeling processes may be relevant to interventions aimed at encouraging young women''s nutrient-dense food intake. [Copyright &y& Elsevier]

Abstract: The main aim of this study was to investigate the effects of food-related beliefs about the healthiness of foods, restrained eating, and weight salience on actual food intake during an ad libitum snack. In a 2 (healthy vs. unhealthy) by 2 (restrained vs. unrestrained eaters) by 2 (weight salient vs. not salient) factorial design, 99 female undergraduate students were invited to taste and rate oatmeal-raisin cookies. Dietary restraint and weight salience did not influence snack intake, but participants ate about 35% more when the snack was regarded as healthy than when it was seen as unhealthy. Ratings of the snack food''s “healthiness,” “capacity to affect weight” and “appropriateness in a healthy menu” also indicated that the “healthy” manipulation was effective. In addition, the “weight salience” manipulation appears to influence perceptions about food differently in restrained versus unrestrained eaters, in that restrained eaters rated the snack food more negatively than unrestrained eaters did when they received weight feedback before eating. Beliefs about the healthiness of foods may thus be of great relevance to both food intake and weight gain. [Copyright &y& Elsevier]

Abstract: Laboratory taste-test studies have shown that social modeling effects on food intake are powerful. The aim of the present study was to examine the degree to which people model food intake in a more naturalistic eating setting. After completing a cover task, female participants (N =102) spent a 15-min break with a female confederate who ate a large amount or a small amount of M&Ms or no M&Ms at all. Further, the confederate had a slim or (subtly manipulated) normal-weight appearance. Females who were exposed to a confederate who ate much consumed more than those who were confronted with a confederate who ate only a little or nothing at all. Although the manipulation of the confederate''s appearance had no significant main effect on the amount of food that participants consumed, a significant interaction effect was found, such that the modeling effect of eating was present only in the normal-weight appearance condition. Our findings suggest that normal-weight young women are more inclined to imitate the food intake of a female confederate if they are more similar to the confederate. [Copyright &y& Elsevier]

Abstract: In order to determine the effects of selective food restriction on subsequent food intake and cravings, participants were randomly assigned to one of three conditions: carbohydrate-restriction, protein-restriction, or control (no restriction). Participants in the restriction conditions were asked to restrict their intake of either complex carbohydrates or animal proteins for 3 days, before coming to the laboratory for an experimental session. During the experimental session, participants’ food intake, cravings, and affect were measured. The results indicated that selective food restriction resulted in selective behavioural consequences. Specifically, carbohydrate-restricted participants consumed more of a high-carbohydrate food than did controls or protein-restrictors, in addition to reporting more cravings for high-carbohydrate foods over the restriction period. Protein-restricted participants reported more cravings for high-protein foods over the restriction period, in comparison to controls and carbohydrate-restrictors; however, protein-restricted participants did not consume more of the particular high-protein food presented to them in the laboratory. The roles of dietary restraint and negative affect in influencing cravings and food intake are discussed. Overall, selective food restriction is demonstrated to have negative psychological and behavioural consequences. [Copyright &y& Elsevier]

Abstract: 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. [Copyright &y& Elsevier]

The contemporary food-rich environment has been consistently linked to unhealthy eating. Emerging research suggests that changing the presentation context of unhealthy foods by introducing a subtle nudge in the form of a healthy food cue may promote healthier dietary choices. This study investigated the effect of the timing of a healthy food cue (before or simultaneously with food options) on food choices. Participants (n = 210) were presented with a pictorial café-style menu displaying a healthy food cue (basket of fruit and vegetables) either on the menu cover or inside the menu, or they received a control menu. Participants were asked to make one choice from each of three menu sections (meals, beverages, afters), and then completed a measure of dietary restraint. As predicted, participants chose a greater proportion of healthy food from the healthy-cue-before menu compared to both the healthy-cue-simultaneous and control menus. Furthermore, this effect was stronger for restrained eaters. The findings demonstrate that the timing of presentation of a healthy food cue is critical, and could be used to inform the design of menus in real-world environments, such as cafés and fast-food outlets, to promote healthier dietary choices. [ABSTRACT FROM AUTHOR]

Abstract There is some evidence from laboratory-based studies that descriptive social-norm messages are associated with increased consumption of vegetables, but evidence of their effectiveness in real-world settings is limited. In two observational field studies taking an ecological approach, a vegetable-related social norm (e.g. "Did you know that most students here choose to eat vegetables with their meal?"), and a health message (e.g. "Did you know that students who choose to eat vegetables have a lower risk of heart disease?") were displayed in two different student canteens. Purchases were observed during three stages: baseline, intervention (when the posters were displayed) and immediate post-intervention (when the posters had been removed). Study 1 (n = 7598) observed the purchase of meals containing a portion of vegetables and Study 2 (n = 4052) observed the purchase of side portions of vegetables. In Study 1, relative to baseline, the social-norms intervention was associated with an increase in purchases of vegetables (from 63% to 68% of meals; OR = 1.24, CI = 1.03–1.49), which was sustained post-intervention (67% of meals; OR = 0.96, CI = 0.80–1.15). There was no effect of the health message (75% of meals at baseline, and 74% during the intervention; OR = 0.98, CI = 0.83–1.15). In Study 2, relative to baseline, there was an effect of both the social norm (22.9% of meals at baseline, rising to 32.5% during the intervention; OR = 1.62, CI = 1.27–2.05) and health message (rising from 43.8% at baseline to 52.8%; OR = 0.59, CI = 0.46-0.75). The increase was not sustained post-intervention for the social norm intervention (22.1%; OR = 0.59, CI = 0.46-0.75), but was sustained for the health intervention (48.1%; OR = 0.83, CI = 0.67–1.02). These results support further testing of the effectiveness of such messages in encouraging healthier eating and indicate the need for larger-scale testing at multiple sites using a randomised-controlled design. [ABSTRACT FROM AUTHOR]

We review the research on the association between personality and dietary restraint as measured by commonly-used self-report assessment instruments (Restraint Scale, TFEQ, DEBQ, and EDE-Q). In order to expand our understanding of the potentially different types of dieters, we examine the different personality profiles that emerge from existing studies of restraint and personality, including associations between restraint and body dissatisfaction and body focus, self-esteem, neuroticism, sensation seeking, impulsivity, perfectionism and narcissism. This research provides some preliminary evidence that different measures of restraint are associated not only with different eating behaviours, but that they capture different personality profiles. [ABSTRACT FROM AUTHOR]

Normative eating cues (portion size, social factors) have a powerful impact on people's food intake, but people often fail to acknowledge the influence of these cues, instead explaining their food intake in terms of internal (hunger) or sensory (taste) cues. This study examined whether the same biases apply when making predictions about how much food a person would eat. Participants (n = 364) read a series of vignettes describing an eating scenario and predicted how much food the target person would eat in each situation. Some scenarios consisted of a single eating cue (hunger, taste, or a normative cue) that would be expected to increase intake (e.g., high hunger) or decrease intake (e.g., a companion who eats very little). Other scenarios combined two cues that were in conflict with one another (e.g., high hunger + a companion who eats very little). In the cue-conflict scenarios involving an inhibitory internal/sensory cue (e.g., low hunger) with an augmenting normative cue (e.g., a companion who eats a lot), participants predicted a low level of food intake, suggesting a bias toward the internal/sensory cue. For scenarios involving an augmenting internal/sensory cue (e.g., high hunger) and an inhibitory normative cue (e.g., a companion who eats very little), participants predicted an intermediate level of food intake, suggesting that they were influenced by both the internal/sensory and normative cue. Overall, predictions about food intake tend to reflect a general bias toward internal/sensory cues, but also include normative cues when those cues are inhibitory. If people are systematically biased toward internal, sensory, and inhibitory cues, then they may underestimate how much food they or other people will eat in many situations, particularly when normative cues promoting eating are present. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: Research suggests that caloric restriction (CR) is beneficial; however, the effects of CR in the context of food cues are unclear. A 2 (food cue vs. no cue)×2 (CR vs. ad lib) between-subjects design was employed to test these effects in 40 rats. It was predicted that cue exposure and CR would induce stress, and that these factors might interact synergistically. The results demonstrated that cue-exposed CR rats weighed less than did non-exposed CR rats. A blunted stress response was evident in CR rats relative to ad lib rats. Finally, cue-exposed rats had higher corticosterone levels and body weight during ad lib feeding than did non-cued rats. These results suggest that both CR and chronic food-cue exposure can be stressful, and the implications of this research are discussed in the context of humans’ ‘obesigenic’ environment. [Copyright &y& Elsevier]

Abstract: This study investigates the effects of the quality of social interaction on modeling of food intake among young women. A two (confederate''s food intake: high versus low) by two (confederate''s sociability: sociable versus unsociable) between-participant factorial design was employed. A total of 100 young women (18–27 years) participated. Findings indicated that young women generally ate more when exposed to a high-intake peer than women exposed to a low-intake peer. However, this modeling effect was only found in the unsociable context. This study underscores the influence of social atmosphere on modeling effects of palatable food intake and suggests that contextual uncertainty or ingratiation strategies may be important in explaining the magnitude of modeling effects. [Copyright &y& Elsevier]

Abstract: The Dutch Eating Behavior Questionnaire Restraint Scale (DEBQ-R) assesses both intentions to restrict food intake (3 items) and actual behavioral restraint (7 items). Studies in general population''s samples have shown that the DEBQ-R is a reliable instrument with all items loading highly on a single factor. The purpose of the present study was to examine the psychometric properties of a two-factor intention-versus-behavior structure of the DEBQ-R in 3 different weight-concerned samples with people from different (over)weight categories (total N=790) using confirmatory factor analysis. A robust two-factor structure emerged in the various samples, generally supporting a distinction between DEBQ-R questions relating to intentions to restrict food intake and actual restrictive behavior. Results obtained in this study are important, because they suggest that a distinction between restrained intention and behavior could help to explain the relation between dietary restraint and external overeating tendencies. Future longitudinal research should examine whether the newly developed dietary restraint scales predict changes in overeating and Body Mass Index (BMI). [Copyright &y& Elsevier]

Previous research has shown that exposure to food cues increases eating, especially in restrained eaters. The present study attempted to determine whether this elevated consumption reflects a general desire to eat in response to food cues, or specific desire/craving for the cued food. Restrained and unrestrained eaters were exposed to the smell of either pizza, cookies, or no smell for 10 minutes, were asked to write their thoughts (corresponding to the smell cue) about pizza, cookies or in general, and were then presented with either pizza or cookies to ‘taste and rate’. Results indicated that restrained eaters are more responsive than are unrestrained eaters to pre-eating exposure to smell and thought cues, eating significantly more after such cues. An interaction with food type, however, indicated that restrained eaters ate more only when the food presented to eat was the same as the prior food cues. Self-reported desire to eat, liking, and craving for a particular food increased somewhat for restrained eaters after exposure to the smell and thought of that food. Restrained eaters'' intake of a food that differed from the pre-eating food cues did not differ from their intake following no prior exposure to food cues. Restrained eaters thus showed a highly specific response to exposure to food cues. [Copyright &y& Elsevier]

There is some evidence from laboratory-based studies that descriptive social-norm messages are associated with increased consumption of vegetables, but evidence of their effectiveness in real-world settings is limited. In two observational field studies taking an ecological approach, a vegetable-related social norm (e.g. "Did you know that most students here choose to eat vegetables with their meal?"), and a health message (e.g. "Did you know that students who choose to eat vegetables have a lower risk of heart disease?") were displayed in two different student canteens. Purchases were observed during three stages: baseline, intervention (when the posters were displayed) and immediate post-intervention (when the posters had been removed). Study 1 (n = 7598) observed the purchase of meals containing a portion of vegetables and Study 2 (n = 4052) observed the purchase of side portions of vegetables. In Study 1, relative to baseline, the social-norms intervention was associated with an increase in purchases of vegetables (from 63% to 68% of meals; OR = 1.24, CI = 1.03-1.49), which was sustained post-intervention (67% of meals; OR = 0.96, CI = 0.80-1.15). There was no effect of the health message (75% of meals at baseline, and 74% during the intervention; OR = 0.98, CI = 0.83-1.15). In Study 2, relative to baseline, there was an effect of both the social norm (22.9% of meals at baseline, rising to 32.5% during the intervention; OR = 1.62, CI = 1.27-2.05) and health message (rising from 43.8% at baseline to 52.8%; OR = 0.59, CI = 0.46-0.75). The increase was not sustained post-intervention for the social norm intervention (22.1%; OR = 0.59, CI = 0.46-0.75), but was sustained for the health intervention (48.1%; OR = 0.83, CI = 0.67-1.02). These results support further testing of the effectiveness of such messages in encouraging healthier eating and indicate the need for larger-scale testing at multiple sites using a randomised-controlled design. [ABSTRACT FROM AUTHOR]