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.     

Self-presentational conflict in social eating situations: a normative perspective

This study explored the degree to which people adhere to norms for "appropriate" eating behavior in social situations. Of particular interest was how people determine what is appropriate behavior when they are faced with conflicting norms within a given situation. Participants tasted cookies while alone or while observed by the experimenter. Furthermore, participants were assigned to either a "no norm" condition in which they were given no indication of how much other people in the study had eaten, an "inhibition norm" condition in which they were led to believe that others had eaten minimally, or an "augmentation norm" condition in which they were led to believe that others in the study had eaten a lot. When they were alone, participants were influenced by the norms; but when they were observed, they ate minimally, regardless of the norms to which they were exposed. It seems that a norm for minimal eating superseded a matching norm which prescribes that people should use the intake of their peers as a guide for appropriate behavior. Implications of these findings and limitations of the study were discussed.     

‘We are always in some form of contact’: friendships among homeless drug and alcohol users living in hostels

Homeless drug and alcohol users are one of the most marginalised groups in society. They frequently have complex needs and limited social support. In this paper, we explore the role of friendship in the lives of homeless drug and alcohol users living in hostels, using the concepts of ‘social capital’ and ‘recovery capital’ to frame the analyses. The study was undertaken in three hostels, each in a different English city, during 2013–2014. Audio recorded semi‐structured interviews were conducted with 30 residents (9 females; 21 males) who self‐reported drink and/or drug problems; follow‐up interviews were completed 4–6 weeks later with 22 participants (6 females; 16 males). Data were transcribed verbatim, coded using the software package MAXQDA, and analysed using Framework. Only 21 participants reported current friends at interview 1, and friendship networks were small and changeable. Despite this, participants desired friendships that were culturally normative. Eight categories of friend emerged from the data: family‐like friends; using friends; homeless friends; childhood friends; online‐only friends; drug treatment friends; work friends; and mutual interest friends. Routine and regular contact was highly valued, with family‐like friends appearing to offer the most constant practical and emotional support. The use of information and communication technologies (ICTs) was central to many participants' friendships, keeping them connected to social support and recovery capital outside homelessness and substance‐using worlds. We conclude that those working with homeless drug and alcohol users – and potentially other marginalised populations – could beneficially encourage their clients to identify and build upon their most positive and reliable relationships. Additionally, they might explore ways of promoting the use of ICTs to combat loneliness and isolation. Texting, emailing, online mutual aid meetings, chatrooms, Internet penpals, skyping and other social media all offer potentially valuable opportunities for building friendships that can bolster otherwise limited social and recovery capital.     

Misperceptions of peer norms as a risk factor for sugar-sweetened beverage consumption among secondary school students

Research has shown that excess calories from sugar-sweetened beverages are associated with weight gain among youth. There is limited knowledge, however, regarding perception of sugar-sweetened beverage consumption norms. This study examined the extent of misperception about peer sugar-sweetened beverage consumption norms and the association of perceived peer norms with personal self-reported consumption. Among 3,831 6th- to 12th-grade students in eight schools who completed anonymous cross-sectional surveys between November 2008 and May 2009, students' personal perception of the daily sugar-sweetened beverage consumption norm in their school within their grade (School Grade group) was compared with aggregate self-reports of daily sugar-sweetened beverage consumption for each School Grade group. The median daily sugar-sweetened beverage consumption from personal reports was one beverage in 24 of 29 School Grade groups, two beverages in four School Grade groups, and three beverages in one School Grade group. Seventy-six percent of students overestimated the daily norm in their School Grade group, with 24% perceiving the norm to be at least three beverages or more per day. Fixed-effects multiple regression analysis showed that the perceived peer sugar-sweetened beverage consumption norm was much more positively associated with personal consumption than was the estimated actual sugar-sweetened beverage consumption norm per School Grade group. Misperceptions of peer sugar-sweetened beverage consumption norms were pervasive and associated with unhealthy sugar-sweetened beverage consumption behavior. These misperceptions may contribute to intake of excess calories, potentially contributing to adolescent obesity. Future research should assess the pervasiveness of sugar-sweetened beverage consumption misperceptions in other school populations as well as causes and consequences of these misperceptions. Health professionals may wish to consider how normative feedback interventions could potentially reduce consumption.     

What Everyone Else Is Eating: A Systematic Review and Meta-Analysis of the Effect of Informational Eating Norms on Eating Behavior

There is interest in the hypothesis that social norms are a determinant of healthy and unhealthy dietary practices. The objective of our work was to assess the weight of evidence that experimentally manipulated information about eating norms influences food intake and choice. This systematic review of experimental studies examined whether providing information about other peoples' eating habits influences food intake or choices. To inform the review, three electronic databases (PsycINFO, MEDLINE, and the Social Sciences Citation Index) were searched during July 2012. A narrative approach was used to synthesize studies that examined the influence of norms on food choice and meta-analyses were used to synthesize the effect that informational eating norms have on quantity of food consumed. Fifteen experimental studies were reviewed. There was evidence that both high intake norms (Z=3.84; P=0.0001; standardized mean difference 0.41, 95% confidence interval 0.20 to 0.63) and low intake norms (Z=2.78; P=0.005; standard mean difference –0.35, 95% confidence interval –0.59 to –0.10) exerted moderate influence on amounts of food eaten. There was consistent evidence that norms influenced food choices; norm information indicating that others make low-energy or high-energy food choices significantly increased the likelihood that participants made similar choices. Information about eating norms influences choice and quantity of food eaten, which could be used to promote healthy changes to dietary behavior.     

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.     

The relationship between friendship factors and adolescent girls' body image concern, body dissatisfaction, and restrained eating

OBJECTIVE: This study examined whether poorer friendship relations predict weight concerns and dietary restraint in adolescent girls. METHOD: Questionnaires were administered to 131 Year 9 and Year 10 girls to assess the relationship between acceptance by friends, perceived social support, friendship intimacy, and perceived impact of thinness on male (PITOF-M) and female (PITOF-F) friendships on the one hand, and body image concern, body dissatisfaction, and restrained eating on the other. RESULTS: Friendship variables contributed significantly to the prediction of body image concern, body dissatisfaction, and restrained eating. The largest unique contribution to prediction was from the PITOF-M. Poor acceptance by friends significantly predicted the PITOF-M and PITOF-F. Whereas heavier girls were more likely to believe being thinner would improve their friendships, they did not experience poorer friendships. DISCUSSION: Results suggest sociocultural risk factors for disordered eating and underline the importance of perceived peer affiliation on girls' body image concern and dieting.     

Social network concordance in food choice among spouses, friends, and siblings

Objectives. We investigated whether eating behaviors were concordant among diverse sets of social ties.Methods. We analyzed the socioeconomic and demographic distribution of eating among 3418 members of the Framingham Heart Study observed from 1991 to 2001. We used a data-classification procedure to simplify choices into 7 nonoverlapping patterns that we matched with information on social network ties. We used correlation analysis to examine eating associations among 4 types of peers (spouses, friends, brothers, and sisters). Longitudinal multiple logistic regression was used to evaluate evidence for peer influences on eating.Results. Of all peer types, spouses showed the strongest concordances in eating patterns over time after adjustment for social contextual factors. Across all peers, the eating pattern most likely to be shared by socially connected individuals was “alcohol and snacks.” Models estimating one''s current eating pattern on the basis of a peer''s prior eating provided supportive evidence of a social influence process.Conclusions. Certain eating patterns appeared to be socially transmissible across different kinds of relationships. These findings represent an important step in specifying the relevant social environment in the study of health behaviors to include eating.Food consumption is incontrovertibly linked with public health outcomes ranging from obesity to cardiovascular disease and diabetes.^1,2 Research has found that eating with others affects what an individual consumes³ and, more recently, that obesity status is influenced by ties in social networks.⁴ Together, this knowledge highlights the value of understanding the roles that relationships play in our eating behaviors. To date, however, there has been little research investigating the relationship between patterns of food consumption and the complex patterns of human connectedness. To what degree is the eating behavior of one''s peers associated with what one eats?Research on commensality and health concordance gives some insight into this question. For instance, eating with others is associated with greater ingestion than when food is consumed alone⁵; friends and family members are associated with greater “social facilitation” than are other kinds of relationships, including co-workers, classmates, lovers, or roommates³; family members are more likely to eat together than friends are⁶; and cognitive dietary restraint, disinhibition, and susceptibility to hunger have a significant familial resemblance.⁷ Research on diet in the context of health concordance has found that newly coupled individuals tend to increase their consumption of fruits and vegetables, low-fat foods, and breakfasts together, while consuming less take-out food,⁸ and that spouses’ nutrient consumption is modestly correlated.⁹ Couples shape one another''s choices, although female partners tend to have more influence over male choices.¹⁰ However, a great deal of what we know of commensality has been gleaned from laboratory research rather than real-world studies of eating behavior, thereby excluding the social environment. Similarly, our knowledge of diet concordance in observational studies has largely issued from small-scale, cross-sectional designs.¹¹Previous work on social networks and health has found that weight status is related to patterns of social relations^4,12 and that drinking behaviors can spread in a social network.¹³ However, whether food consumption per se is subject to similar forms of peer influence in a network setting has not been examined. Our objective was to investigate whether connections with particular kinds of intimate relations (spouses, friends, and siblings) were predictive of eating patterns of connected individuals in a large prospective cohort study over time. To address this question, food patterns were first enumerated from food-frequency questionnaires. We then performed a series of correlation analyses to assess food pattern concordance, and we fit a series of longitudinal multiple logistic regression models to test for peer influence on eating among close social contacts.     

Patterns of food selection during meals in women with bulimia

Eating behavior of women with bulimia was compared with that of control subjects who had no eating disorders. Both groups were presented with two buffet-style multiple-item meals. In one meal subjects were instructed to eat normally and in the other they were instructed to eat as much as they could. The eating patterns of patients differed from control subjects in the quantity of food selected and in the rate of eating. During the binge meal, patients spent more of their meal time eating dessert and snacks than did control subjects and began their dessert and snack consumption earlier than control subjects. Patients distributed their meat consumption more evenly across the meal, whereas control subjects ate meat predominantly early in the meals. Most patients consumed either more or less than control subjects when not binge eating, indicating that the eating disturbances in bulimic patients are not confined to episodes of binge eating.     

Social Modeling and Eating Behavior—A Narrative Review

Social modeling of eating is the adjustment of the amount of food eaten to the intake of the accompanying person. In this paper we provide a narrative review of literature on social modeling of eating with a particular focus on recent studies. Firstly, we describe the structure of a typical modeling experiment. Secondly, we present a variety of research in this field: experiments with various types of confederates, experiments aimed at the evaluation of the influence of gender, partner’s body weight, type of food, hunger, personal characteristics, etc. Thirdly, we present practical implications of this knowledge. The common conclusion is that social modeling of eating occurs in different situations and consumption is adapted to the standards established by the eating partner, but is not their direct reflection. Social influence of eating is not restricted to "artificial" laboratory situations; social modeling and social norms manipulations may be used to change people’s dietary practices, especially in children and young adults. Within the home environment parental modeling has been shown to promote children’s snacking and fruit and vegetable consumption. Social modeling may be used in nutrition interventions aimed at the improvement of children’s diet and in obesity prevention programs.     

The shaping role of hunger on self-reported external eating status

As people are relatively incompetent in assessing the impact of visceral states on their behavior, two studies tested the hypothesis that hunger affects the extent to which people assess themselves as external eaters. In Study 1 participants’ current self-reported hunger states were linked to their scores on an external eating scale. Hungrier participants perceived themselves more strongly as external eaters. In Study 2 hunger was experimentally manipulated, after which self-reported external eating was assessed. Hunger was found to affect people's self-reported external eating status, such that hungry participants scored higher and above the average norm score on external eating compared to satiated participants, who scored below this average norm score. The key implications of these findings are discussed.     

The Influence of Physical and Social Contexts of Eating on Lunch-Time Food Intake Among Southern Ontario,Canada, Middle School Students

BACKGROUND: Among students, little is known about the physical and social context of eating lunch. The objective of this study was to determine if food intake (including the type of food and beverages and portion sizes) was associated with specific aspects of the physical and social lunch environment (location, with whom lunch was consumed, who prepared the food, and where the food was originally purchased). METHODS: A total of 1236 participants (males = 659, females = 566) in grades 6 (n = 359), 7 (n = 409), and 8 (n = 463) from southern Ontario, Canada, completed the Food Behavior Questionnaire during the 2005–2006 academic year. RESULTS: A total of 8159 foods and 2200 beverages were consumed during the lunch meal, which contributed to 552 kcal (SD = 429) or 30% (SD = 16) of total daily energy intake (kcal/day). Higher amounts of energy, meats and alternatives, other foods, fried foods, and pizza were consumed when participants ate in between places or at a restaurant/fast food outlet (compared with at home or school, p < 0.05) and/or when prepared by friends or others (compared with themselves or family members, p < 0.05). A large number of participants (46%) reported consuming sugar-sweetened beverages during lunch, despite a school board–level policy restricting the sales of “junk food,” which appears to be brought from home. CONCLUSIONS: Our findings support schools in policy efforts that restrict fast food access (by leaving school grounds, preventing fast food companies from coming onto school grounds, or restricting sugar-sweetened beverage sales in vending machines) and that eating in between places should be discouraged.     

Homophily and Contagion as Explanations for Weight Similarities Among Adolescent Friends

Purpose

To determine whether weight-based similarities among adolescent friends result from social influence processes, after controlling for the role of weight on friendship selection and other confounding influences.

Methods

Four waves of data were collected from a grade 8 cohort of adolescents (N = 156, mean age = 13.6 years) over their initial 2 years of high school. At each wave, participants reported on their friendship relations with grade-mates and had their height and weight measured by researchers to calculate their body mass index (BMI). Newly developed stochastic actor-oriented models for social networks were used to simultaneously assess the role of weight on adolescents' friendship choices, and the effect of friends' BMIs on changes in adolescent BMI.

Results

Adolescents' BMIs were not significantly predicted by the BMI of their friends over the 16 months of this study. Similarities in the weights of friends were found to be driven predominantly by friendship selection, whereby adolescents, particularly those who were not overweight, preferred to initiate friendships with peers whose weight status (overweight/nonoverweight) was the same as their own.

Conclusions

Weight-based similarities among friends were largely explained by the marginalization of overweight adolescents by their peers, rather than by the “contagion” of excess weight among friends. These findings highlight the importance of adequately modeling friendship selection processes when estimating social influence effects on adiposity.     

Peer Influence on Marijuana Use in Different Types of Friendships

PurposeAlthough several social network studies have demonstrated peer influence effects on adolescent substance use, findings for marijuana use have been equivocal. This study examines whether structural features of friendships moderate friends' influence on adolescent marijuana use over time.MethodsUsing 1-year longitudinal data from the National Longitudinal Study of Adolescent Health, this article examines whether three structural features of friendships moderate friends' influence on adolescent marijuana use: whether the friendship is reciprocated, the popularity of the nominated friend, and the popularity/status difference between the nominated friend and the adolescent. The sample consists of students in grade 10/11 at wave I, who were in grade 11/12 at wave II, from two large schools with complete grade-based friendship network data (N = 1,612).ResultsIn one school, friends' influence on marijuana use was more likely to occur within mutual, reciprocated friendships compared with nonreciprocated relationships. In the other school, friends' influence was stronger when the friends were relatively popular within the school setting or much more popular than the adolescents themselves.ConclusionsFriends' influence on youth marijuana use may play out in different ways, depending on the school context. In one school, influence occurred predominantly within reciprocated relationships that are likely characterized by closeness and trust, whereas in the other school adopting friends' drug use behaviors appeared to be a strategy to attain social status. Further research is needed to better understand the conditions under which structural features of friendships moderate friends' influence on adolescent marijuana use.     

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.     

Smoking cessation and stress among teenagers

The authors describe the experience of quitting smoking, focusing on the obstacles youth struggle with, based on individual interviews and focus groups with 54 teenagers in New York City. A major obstacle was the belief that people should stop smoking forever. The youth had to cope with temptation, frequent and often intense urges or cravings for cigarettes, and lack of social support from their family and friends. The young participants not only had to cope with general life stresses without being able to use cigarettes to reduce tensions but also had to contend with new stressful situations, such as friends who put them down for not smoking. In addition, the teens had to give up things that were important to them, such as friendships, during their quit attempts. The study describes how quitting can be a much more stressful experience for youth than research typically acknowledges. The authors discuss public health implications.