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

Effects of bitten food images in marketing communications

Marketing communications (e.g., food packages, restaurant menus, coupons, social media posts) often include images of bitten and non-bitten (i.e., complete) foods. Taking an empirics first approach, the current research explores how and why these images influence consumers. A field study shows a higher redemption rate for discount coupons featuring a bitten (vs. non-bitten) food. However, a controlled online study fails to replicate this effect. Two additional preregistered studies shed light on the inconsistent results observed online and in the field by identifying two competing mechanisms catalyzed by bitten food images. Bitten food images lead to vicarious enticement, an automatic process in which a viewer makes sense of a bitten food image by picturing someone approaching and tasting the food, as well as emotional conflict (i.e., the simultaneous activation of positive and negative thoughts and feelings). While vicarious enticement has a positive impact on product responses, emotional conflict has a negative impact. The effect of bitten (vs. non-bitten) food images on product responses appears to depend on the strength of these two mechanisms in a given context. These findings yield insights for researchers examining visual characteristics of food images as well as advertisers designing marketing communications.

Social norms and young adults' self-reported meat and plant-based meal intake: Findings from two online cross-sectional studies

Plant-based eating is beneficial for human and planetary health. It is important to identify factors which may encourage people to reduce meat, and increase plant-based meal intake. Perceived social norms are associated with meat and plant-based meal intake in adults, however, less is known about the relationship between perceived social norms and young adults' own self-reported meat and plant-based eating in general, and in different social contexts. Across two online studies we examined this. In Study 1 (n = 217 young adults, aged 18-25 years, mean age = 19.50 years, SD = 1.37 years, mean BMI = 24.21, SD = 5.45, 91% cisfemale, 92.0% omnivores), perceived descriptive (the perceived behaviour of others) and injunctive (the perceived approval of others) norms were measured in general. In study 2 (n = 151 young adults aged 18-25 years, mean age = 19.62 years, SD = 1.50 years, mean BMI = 24.32, SD = 4.99, 88.8% cisfemale, 71.1% omnivore), perceived descriptive and injunctive norms were examined in a variety of social contexts. In Study 1, perceived descriptive norms about friends were associated with self-reported meat, and descriptive norms about peers and friends, and injunctive norms about friends were positively associated with self-reported plant-based meal intake. In Study 2, descriptive norms about friends were associated with self-reported meat intake in fast-food restaurants and at friends' houses, and injunctive norms about friends were associated with meat intake in restaurants. There were no other significant associations between either type of social norm and meat or plant-based meal intake. We provide the first evidence that peers and friends may be relevant for plant-based meal intake, and only friends may be relevant for meat intake. Further research is needed to examine people's actual food intake, and in longitudinal studies to rule out reverse causality.

I'll have what She's having (but not what They're having): The moderating role of group membership in the effect of social norms on food choice in an online environment

The modern food-rich environment has contributed to the rise of unhealthy diets linked to noncommunicable diseases. Previous in-person research has found that the effect of social norms on food intake is greater when set by a perceived in-group member relative to an out-group member. Given recent increased social media use, we investigated whether this effect of group membership extends to food choices and to normative information presented remotely online. Participants (N = 179 female university students, 18-32 years) viewed a Facebook page pertaining to either their university (in-group) or a rival university (out-group). They were presented with either a healthy or an unhealthy norm via a post in which a student discussed their order at a café on the relevant campus. Food choice was assessed through an online menu where participants were asked to order one main, side, and dessert dish. As predicted, participants who viewed the healthy norm ordered a higher percentage of healthy items (especially in the desserts category) relative to those who viewed the unhealthy norm. However, this effect was significant only for those in the in-group condition; there was no such pattern for participants in the out-group condition. These findings provide insight into the role of group membership in the effect of social norms, and have practical implications regarding the design of identity-based social media health campaigns to promote healthier eating behaviours.

Ethnic differences in meat consumption attitudes, norms and behaviors: A survey of White, South Asian and Black ethnic groups in the UK

A reduction in meat consumption is necessary to mitigate negative impacts of climate change and adverse health outcomes. The UK has an increasingly multi-ethnic population, yet there is little research on meat consumption habits and attitudes among ethnic groups in the UK. We ran a survey (N = 1014) with quota samples for ethnic groups and analyzed attitudes, behaviors and norm perceptions of White, South Asian and Black British respondents. Most respondents believe overconsumption of red and processed meat has negative impacts on health (73.3%) and the environment (64.3%).South Asian respondents were statistically significantly less likely to be meat eaters than White respondents (OR = 0.44, 95% CIs: 0.30-0.65, t = -4.15, p = 0.000), while there was no significant difference between White and Black respondents (OR = 1.06, 95% CIs: 0.63-1.76, t = 0.21, p = 0.834). Both South Asian (OR = 2.76, 95% CIs: 1.89-4.03 t = 5.25, p = 0.000) and Black respondents (OR = 2.09, 95% CIs: 0.1.30-3.35, t = 3.06, p = 0.002) were significantly more likely to express being influenced by friends and family in their food choices than White respondents. South Asian (OR = 3.24,95% CIs: 2.17-4.84, t = 5.74, p = 0.000) and Black (OR = 2.02,95% CIs: 1.21-3.39, t = 2.69, p = 0.007) respondents were also both significantly more likely to report they would want to eat similarly to their friends and family than White respondents. Statistical analyses suggested some gender and socioeconomic differences across and among ethnic groups, which are reported and discussed. The differences in meat consumption behaviors and norm conformity between ethnic groups raises the prospect that interventions that leverage social norms may be more effective in South Asian groups than Black and White groups in the UK.

What factors influence sustainable and healthy diet consumption? A review and synthesis of literature within the university setting and beyond

Globally, typical dietary patterns are neither healthy nor sustainable. Recognizing the key role of dietary change in reducing noncommunicable disease risk and addressing environmental degradation, it is crucial to understand how to shift individuals toward a sustainable and healthy diet (SHD). In this literature review, we introduced the concept of a SHD and outlined the dietary behaviors necessary to transition toward SHD consumption; we reviewed the literature on factors that may influence sustainable (and unsustainable) dietary behaviors in adults; and we developed a novel scoring system to rank factors by priority for targeting in future research. Given the significant potential to promote a sustainable and healthy dietary transition on the university campus-where factors that may impact dietary behaviors can be targeted at all levels of influence (i.e., individual, interpersonal, environmental, policy)-we narrowed our focus to this setting throughout. Aided by our novel scoring system, we identified conscious habitual eating, product price, food availability/accessibility, product convenience, self-regulation skills, knowledge of animal ethics/welfare, food promotion, and eating norms as important modifiable factors that may influence university students' dietary behaviors. When scored without consideration for the university population, these factors were also ranked as highest priority, as was modified portion sizes. Our findings offer insight into factors that may warrant attention in future research aimed at promoting SHDs. In particular, the high-priority factors identified from our synthesis of the literature could help guide the development of more personalized dietary behavioral interventions within the university setting and beyond.

Exploring the influence of context on social norms around Australian parents' food provision using story completion

OBJECTIVE

To explore the differences in social norms around parents' food provision in different provision contexts and by demographics.

DESIGN

Qualitative study using story completion methodology via an online survey in September 2021. Adults 18+ with or without children were randomised to one of three story stems focusing on food provision in different contexts; food provision at home (non-visitor), with visitors present and with the involvement of sport. Stories were coded and themed using thematic analysis. A content analysis was performed to determine count and frequency of codes in stories by participant demographics and story assumptions.

SETTING

Australia.

PARTICIPANTS

Adults (n 196).

RESULTS

Nine themes were identified from the data resulting in four social norms around providing healthy foods and justifying non-adherence to healthy eating guidelines, evolution of family life and mealtime values, the presence of others influencing how we engage with food provision and unhealthy foods used as incentives/rewards in sport. Following content analysis, no differences of themes or norms by participant demographics or story assumptions were found.

CONCLUSIONS

We identified pervasive social norms around family food provision and further identified how contextual factors resulted in variations or distinct norms. This highlights the impact context may have on the social norms parents face when providing food to their children and the opportunities and risks of leveraging these social norms to influence food choice in these contexts. Public health interventions and practitioners should understand the influence of context and social environments when promoting behaviour change and providing individualised advice. Future research could explore parents' experiences of these norms and to what extent they impact food choice.

How perceptions of meat consumption norms differ across contexts and meat consumer groups

Social norm perceptions are implicit standards describing what is typically done or seen as acceptable and have shown to be important both in sustaining meat consumption as well as facilitating meat reduction. Norm perceptions depend on individual differences and the contexts (e.g., supermarket, restaurant). Yet, evidence how norm perceptions differ within and across individuals is scarce. The primary aim of this study was to investigate how descriptive, injunctive, and personal norms perceptions favouring meat consumption differ across contexts and meat consumer groups. The second aim was to investigate how generic dynamic norm perceptions vary across meat consumer groups. British meat eaters (n = 1205, 25-65 years) participated in an online cross-sectional survey. Weekly meat, fish and meat substitute consumption was measured with the adapted Oxford Meat Frequency Questionnaire. All but dynamic norm perceptions were measured for the supermarket, restaurant and worksite cafeteria context. Dynamic norms were measured without a specified context. A two-step cluster analysis was conducted to identify meat consumer groups. Descriptive norm perceptions favouring meat consumption were strongest in supermarket and restaurant contexts, compared to the worksite cafeteria. Injunctive and personal norms favouring meat consumption were both perceived strongest in the supermarket, followed by the restaurant, and least in the worksite cafeteria context. Four meat consumer groups were identified and those with higher meat intake (i.e., Meat lovers and Exceeders) perceived norms favouring meat consumption stronger and norms favouring meat avoidance weaker than the groups with lower meat intake (i.e., Flexitarians and Moderates). While norm perceptions differed between meat consumer groups, the pattern of contextual differences is similar for these meat consumer groups. Our findings underscore the importance of considering contexts and meat consumer groups in efforts to reduce meat consumption.

Is it all due to peers? The influence of peers on children's snack purchase decisions

The objective of this study is to examine whether the presence of peers has an impact on children's snack purchasing decisions. In particular, the research analyzes whether the company of a classmate or friend influences children's brand awareness and price perception, and how these factors affect their snack purchases. An incentive-based discrete choice experiment was conducted with snacks varying in price, brand, and healthiness, using the presence or absence of peers as a between-subject treatment. The data was analyzed using mixed logit models and a multinomial logit model. A total of 128 primary school children aged 8 to 10 years were included in the final data analysis. The findings show that the presence of peers strongly influences children's snack purchase decisions, particularly with respect to product type and price. The results highlight that children tend to conform to the group's decision, highlighting that social influence plays a crucial role in shaping children's decision-making processes. This study is the first to investigate the influence of peers on children's actual purchase decisions, thereby extending previous knowledge of the impact of peers on primary school children to the market domain.

Understanding the behavioral determinants of adolescents' water consumption: A cross-country comparative study

Substituting the consumption of sugar-sweetened beverages (SSB) with that of water can have a positive effect on adolescents' health. However, despite the attention on this topic in the Global North, it is relatively understudied in other regions of the world, such as the Caribbean. To guide the development of future interventions, understanding the factors determining water consumption among Caribbean adolescents is important. This study examined the behavioral determinants of water consumption among adolescents in Aruba (the Caribbean) and compared them to those in the Netherlands (Western Europe). We used a theoretical model that integrates the dominant theoretical perspectives in the field of public health, including theories of planned behavior, social norms, and intrinsic motivation. This cross-country study included 1,584 adolescents from Aruba and the Netherlands (52% girls; M = 12.34 years; SD = 2.14). The data were analyzed using regression analyses. This study found that in Aruba, adolescents with higher scores of intrinsic motivation, friends' descriptive norms, attitudes, and behavioral control regarding water consumption drank more water. Moreover, the associations between water consumption and both intrinsic motivation as well as friends' descriptive norms for adolescents in Aruba were stronger than those found in the Netherlands. These associations imply that it is even more important for Aruban adolescents than Dutch adolescents to be intrinsically motivated or to perceive their friends often consuming water to drink more water. The cross-country comparison implies that future interventions in Aruba aimed at increasing adolescents' water consumption as an alternative to SSB should focus on enhancing their intrinsic motivation while considering their friends' social norms.

What motivates German consumers to reduce their meat consumption? Identifying relevant beliefs

High levels of meat consumption cause problems related to public health, the environment, and animal welfare. Therefore, it is crucial to improve our understanding of the drivers and barriers involved in reducing meat consumption. Using the Theory of Planned Behavior (TPB), we examined to what extent attitude, subjective norm, and perceived behavioral control (PBC) affect intention and willingness to reduce meat consumption. In line with the TPB and going beyond existing literature, we also explored which specific beliefs determine these three constructs. In 2021, we conducted an online survey with a sample representative of the German population (N = 1093). Hierarchical regression models revealed that after controlling for sociodemographic characteristics, the TPB constructs explained 55% of the variance in intention and 61% of the variance in willingness. Importantly, each of the three TPB constructs affected intention and willingness to reduce meat consumption, with attitude having the largest impact. Habit strength and past behavior in addition to the TPB constructs did not improve prediction. Multiple linear regression models showed that attitude was determined by the beliefs that reducing meat consumption leads to a healthier diet, a reduced risk of developing certain diseases, a more natural diet, and the feeling of missing meat. In contrast, environmental and animal welfare concerns showed no significant effect on attitude. Both family and friends contributed to the perceived social pressure. The beliefs of being able to prepare meat-free meals, having enough time to spend on one's diet, and being able to easily purchase meat substitutes led to higher PBC. Based on these findings, we provide recommendations for intervention strategies and derive implications for future research.

Booming the bugs: How can marketing help increase consumer acceptance of insect-based food in Western countries?

Edible insects could be a promising answer to the question of how to feed a growing human population with a healthier and more sustainable source of protein. Despite the increasing interest in entomophagy in food science and industry, however, consumer acceptance for insect-based food products remains low in Western countries. This systematic review provides a comprehensive and timely overview of studies relevant for researchers, practitioners and other stakeholders involved in the marketing of these products. Reviewing data from 45 selected studies, we focus on marketing measures tested for their influence on Western consumers' preference, acceptance, willingness to try, eat and/or buy insect-based food products. Organising the findings according to the 4Ps of the marketing mix framework, five main ways of enhancing the appeal and acceptance of insect-based food products are discussed: 1) developing product attributes that align with the specific preferences of target consumers; 2) a more subtle labelling of the presence of insects; 3) using value-added or competition-based pricing strategies; 4) making products consistently available in the marketplace; and 5) promoting products more effectively through advertising, tasting activities, and social influence. The heterogeneity we find among the studies, whether due to differences in the products researched, in sampling countries, or in data-collection methods, indicates key research gaps for future studies to address.

Association between health risk behaviors and food consumption in adolescents

The study aims to evaluate the association between substance use and social isolation with food consumption in adolescents. A cross-sectional study was conducted with 2,040 adolescents from a medium-sized city in Brazil. The exposures assessed were the use of alcohol, tobacco, and other substances, and social isolation. The outcomes were the regular consumption (≥5 times/week) of beans, fruit/fruit salad, candies, and soft drinks, and an unhealthy eating score. The association between health risk behaviors and food consumption was assessed through logistic and linear regressions. Regular users of alcohol were more likely to have regular consumption of candies and soft drinks, and those who used tobacco regularly were less likely to have regular bean consumption and more likely to have regular candies consumption. The use of at least one substance was negatively associated with regular bean consumption and positively associated with regular consumption of sweets and soft drinks. Socially isolated adolescents were less likely to have regular bean consumption. Substance use was positively associated with the unhealthy eating score. In conclusion, substance use and social isolation were associated with less regular consumption of healthy food markers and greater regular consumption of unhealthy food markers.

Nosotros mismos nos estamos matando/We are the ones killing ourselves: Unraveling individual and network characteristics associated with negative dietary acculturation among Mexican Americans in New York City

BACKGROUND

Research on negative dietary acculturation among Mexican-Americans has mostly focused on individual-level processes and has largely ignored the role of social networks.

METHODS

This mixed-method study used an egocentric network approach and derived 1620 personal ties of self-identified Mexican adults in New York. 24-hour dietary recalls were used to derive a total Healthy Eating Index (HEI) and subscores. The qualitative portion generated narratives around who helps or hinders their efforts to eat healthfully.

RESULTS

At the individual level, age at which participants migrated to the U.S. was negatively associated with total HEI (β = -0.39, p < .01). An annual income below $30,000 was positively associated with total HEI (β = 0.25, p < .05) and with HEI fruit subscores (β = 0.25, p < .05). Acculturative stress was negatively associated with HEI fruit (β = -0.29, p < .05) and refined grain subscores (β = -0.34, p < .01). At the network level, the proportion of network members who consumed traditional Latino diets was negatively associated with total HEI and HEI refined grains subscores (β = -0.39, p < .001; and β = -0.23, p < .05; respectively). In contrast, the proportion of alters who lived in another country was positively associated with HEI dairy subscores (β = 0.25, p < .05). Juxtaposing qualitative participants' visual representation of their total HEI scores with their lay interpretations of healthy and unhealthy eating matched public health messages of reducing sugar, red meat intake, and processed foods. However, participants felt that this could only be achieved through restriction rather than balance. Qualitative narratives also elucidated how dietary acculturation and income could help shape dietary quality in unexpected ways.

CONCLUSIONS

This study found evidence of negative dietary acculturation and showcases the complex ways in which both individual- and network-level processes help shape dietary choices for Mexican-Americans.

The effect of social norms on vegetarian choices is moderated by intentions to follow a vegetarian diet in the future: Evidence from a laboratory and field study

Social norms could be a tool in dietary transition toward more sustainable diets, but the results of social norms interventions aimed at encouraging the selection of plant-based foods to date have been inconsistent. One reason for this might be because there are important moderating factors that have yet to be investigated. Here we examine social modeling of vegetarian food choices and test whether modeling is dependent upon individual intentions to follow a vegetarian diet in the future in two different settings. In a laboratory study of 37 women, participants with low intentions to become a vegetarian consumed fewer plant-based foods in the presence of a vegetarian confederate, compared to eating alone. In an observational study of 1,037 patrons of a workplace restaurant, participants with a higher score of on vegetarian intentions had a greater likelihood of taking a vegetarian main course or starter, and a vegetarian social norm was associated with a greater likelihood of a vegetarian choice for the main course but not for the starter. These data suggest that participants with low intentions to follow a vegetarian diet may exhibit reactance against an explicit vegetarian norm in an unfamiliar context (as in Study 1) but that general norm following regardless of dietary intentions be more likely when it is conveyed implicitly in a familiar context (as in Study 2).

The Correlation between Social Media Addiction and Emotional Eating during the COVID-19 Quarantine Period

This study was conducted with 458 participants. The demographic and health information of the participants along with the Social Media Addiction, Emotional Eating Scale were obtained. The level of social media addiction in adults was moderate, and women were more interested in social media than men. As the average age of participants increased, the virtual tolerance, virtual communication, social media scores decreased (p < .05). The study found that 51.6% of individuals with emotional eating tendencies happened to be obese. The social media addiction scale scores of those with emotional eating tendencies were higher than those without emotional eating tendencies (p < .05).

Masculinity Matters for Meat Consumption: An Examination of Self-Rated Gender Typicality, Meat Consumption, and Veg*nism in Australian Men and Women

Previous research shows that men eat more meat than women. We explore the extent to which self-rated gender typicality explains differences in meat consumption intentions and behaviour. We recruited a large sample (N = 4897) of Australian men and women to complete an online survey about their attitudes and intentions regarding meat consumption and abstention and measured their self-rated gender typicality (the extent men view themselves as masculine, and women view themselves as feminine). We used moderated regression analyses to investigate self-rated gender typicality as a moderator of the relationship between gender and meat-related variables. We demonstrated that for men, identifying as more masculine was associated with a lower likelihood of reducing meat consumption or considering veg*nism, and a greater belief that eating meat is normal. We also found that men, and those with more gender-typical self-ratings (regardless of gender), viewed meat as more natural, necessary, and nice. These findings suggest that self-rated gender typicality may be relevant for understanding gender differences in meat consumption behaviours. Appeals to adopt low- or no-meat diets may be more effective if they consider the ways Australian diets are interconnected with genders and identities. Increasing acceptance of alternative masculinities, and developing masculinity-friendly advertising of plant-based foods, could be useful in promoting meat reduction.

Psychological Pathways Through Which Social Norms and Social Identity Influence Eating Behavior: Testing a Conceptual Model

BACKGROUND

Although interventions frequently promote healthy eating, failing to consider psychosocial factors, such as social norms, may limit the effectiveness of these efforts. Perceived social norms are a well-documented determinant of eating behavior; however, there is limited understanding of the processes through which, and for whom, this relationship emerges. Using identity-based motivation as a theoretical framework, we present a conceptual model identifying one route through which descriptive social norms-beliefs about how others behave-predict eating behavior, and test whether this process varies across social identities (e.g., self-perceived weight status).

METHOD

Structured telephone interviews were conducted for a national sample of non-diabetic adults who identified as non-Hispanic White, non-Hispanic Black, or Mexican American (n = 990).

RESULTS

Multigroup SEM analysis comparing individuals who self-identified as overweight (versus "about the right weight" and underweight) demonstrated that perceiving descriptive social norms that people do not eat healthy foods predicted greater perceived barriers to eating healthy foods. Perceived barriers, in turn, predicted stronger beliefs that body weight is uncontrollable, and this relationship was stronger for participants who self-identified as overweight (relative to participants who did not identify as overweight). These beliefs subsequently predicted greater self-reported consumption of unhealthy foods (e.g., sweets), but did not predict consumption of fruits or vegetables.

CONCLUSIONS

This study extends our understanding of a psychosocial process that predicts consumption of unhealthy foods and underscores the importance of social identities for shaping responses to perceived norms.

Social Environmental Predictors of Lapse in Dietary Behavior: An Ecological Momentary Assessment Study Amongst Dutch Adults Trying to Lose Weight

BACKGROUND

When losing weight, most individuals find it difficult to maintain a healthy diet. Social environmental conditions are of pivotal importance in determining dietary behavior. To prevent individuals from lapsing, insight in social environmental predictors of lapse in dietary behavior is needed.

PURPOSE

Identify social environmental predictors of lapse in dietary behavior, using ecological momentary assessment (EMA) amongst Dutch adults trying to lose weight.

METHODS

Adults (N = 81) participated in two 7-day EMA weeks. Six times a day semi-random prompts were sent. At each prompt, participants indicated whether a lapse had occurred and responded to questions assessing social support, descriptive norm, injunctive norm, social pressure, presence of others, and current location. Generalized estimating equations were used to examine associations with lapse.

RESULTS

Injunctive norm (OR = 1.07, 95% CI = 1.03-1.11), descriptive norm (OR = 1.04, 95% CI = 1.02-1.07), and social pressure (OR = 1.09, 95% CI = 1.05-1.14), all toward diverting from diet plans, predicted lapses. Social support toward sticking to diet plans and presence of others did not predict lapses. When controlling for a prior lapse, all other associations became nonsignificant. Lapses occurred most often at home and gradually occurred more often during the day.

CONCLUSIONS

Traditional public health perspectives have mainly focused on individual choice and responsibility for overweight related unhealthy lifestyles. This study shows that there may be opportunities to enhance intervention programs by also focusing on social norms and social pressure. The involvement of partners or housemates may create more awareness of the impact of (unintentional) social pressure on risk of lapsing, and reduce the level of exerted social pressure.

Regional Living Conditions and Individual Dietary Characteristics of the Russian Population

The goal of our study was to examine the effects of the regional characteristics of the living environment on individual a priori and a posteriori dietary patterns of the Russian population. For the analysis, we used cross-sectional data from the Epidemiology of Cardiovascular Diseases in the Regions of the Russian Federation study from 2013-2014. The sample included 18,054 men and women 25-64 years of age from 12 regions. Based on the frequency of consumption of basic foods, four a posteriori empirical dietary patterns (EDPs), along with an a priori cardioprotective dietary pattern (CPDP), were identified. To describe the regional living environment, five regional indices were used. Adherence to the meat-based EDP was directly associated with deterioration of social living conditions and a more northerly location for the region of residence. The probability of a CPDP increased with greater deterioration of social living conditions, aggravation of demographic crises, and higher industrial development in the region, as well as with declines in the economic development of the region, income, and economic inequality among the population. We detected several gender-dependent differences in the associations established. The patterns revealed reflect the national dietary preferences of Russians, and the regional indices characterize the effect of the living environment.

The influence of social norms on anticipated snacking: An experimental study comparing different types of social norms

Previous studies have found that social norms affect eating behavior for different types of social norm measures and manipulations as well as different types of eating behavior. The current study investigated the effects of descriptive, injunctive, and liking norms on intentions to consume healthy snacks and anticipated snack choice, compared to a no-norm control condition. Moreover, we distinguished between descriptive norms that stress the frequency versus the quantity of food consumption. An experiment was conducted among 189 young adults. It was hypothesized that participants who received a descriptive quantity or frequency norm would intend to consume, and make an anticipated selection of, more low-calorie snacks than participants who received a no-norm control message. Due to inconsistency or lacking evidence regarding the effects of the other types of norms on eating behavior, no hypotheses were formulated for the injunctive and liking norm conditions. The hypothesis was partly confirmed. Descriptive quantity and frequency norms did not result in a stronger intention to consume healthy snacks in the upcoming week, but they did result in lower-calorie snack choices when people were asked to select three snacks that they planned to eat on the following day. No other differences between the conditions were found. These findings show that emphasizing both how much and how often most other people consume healthy foods affects anticipated healthy food choices. This can provide health professionals more options to mobilize the power of descriptive social norms for affecting health behavior change.

The influence of social norms in the context of reducing sugar-sweetened beverages consumption

OBJECTIVES

This study aimed to examine the factors associated with low sugar-sweetened beverage (SSB) consumption and intention to avoid these products as well as investigate the role of different types of social norms in the adoption of this behaviour.

STUDY DESIGN

This study reports the results of a secondary data analysis from a cross-sectional telephone survey.

METHODS

A total of 1000 adults were randomly recruited in the province of Québec, Canada, using a random-digit dialling procedure. Eligibility criteria were to be aged between 18 and 64 years; able to answer a questionnaire in French or English; and to reside in the province of Québec. SSB consumption, social norms and variables from the theory of planned behaviour were assessed by means of a questionnaire. Logistic regression analyses were conducted to examine factors associated with behaviour and intention.

RESULTS

Consuming <1 SSB per day was significantly associated with intention, perceived behavioural control, and risk perception about tooth decay. Descriptive (perceived prevalence in the close surroundings of one person) and perceived societal norms (perceived broad societal approval/disapproval of the behaviour) were associated with behaviour. All theory of planned behaviour variables (including injunctive norm) and risk perception pertaining to chronic diseases predicted intention to avoid the consumption of ≥1 SSB per day. Sex, age, income, and risk perception pertaining to chronic diseases were associated with perceived societal disapproval of SSB consumption.

CONCLUSIONS

This study confirms the importance of social norms in the prediction of SSB consumption but also highlights the need to address motivation and capacities in public health interventions to reduce SSB consumption.

Exposure to images showing (non)adherence to physical distancing rules: Effect on adherence behavior and perceived social norms

Introduction

Adherence to behavioral measures such as physical distancing are key to mitigating the effects of viral pandemics such as the COVID-19 pandemic. Adherence depends in part on people’s perception of what others do (descriptive norms) or approve of (injunctive norms). This study examines the effects that exposure to images depicting people following or breaking physical distancing rules have on perceptions of descriptive and injunctive norms and subsequent adherence behavior.

Methods

An online between-subjects experiment (n = 315) was conducted, in which participants were exposed to a set of five photographs of different public spaces in which people either did or did not adhere to physical distancing rules (pre-registration: https://www.osf.io/uek2p). Participants’ adherence behavior was measured using a triangulation of measures (incentivized online behavioral task, vignettes, intention measure). Perceptions of relevant social norms were also measured.

Results

Mann-Whitney tests showed no effects of condition on perceptions of descriptive and injunctive norms or on adherence behavior. Linear regressions showed that both component paths of the indirect effect (condition on norm perceptions, and norm perceptions on adherence behavior) were non-significant, hence mediation analyses were not conducted.

Conclusions

Exposure to images of people following (compared to breaking) physical distancing rules did not affect adherence to such rules or perceived norms. We surmise that a single exposure to such images, especially in the context of COVID-19, is insufficient to affect behavior. We therefore recommend performing a comparable experiment in which participants are exposed repeatedly to images showing people (non)adhering to a specific behavior in a particular context for a longer period.

Investigating the impact of eating norms and collective autonomy support vs. collective control on unhealthy eating and its internalization

Our eating behaviors are highly influenced by those of individuals surrounding us and the groups we belong to. The first goal of this experiment was to determine how social norms that encourage (pro-) vs. discourage (anti-) unhealthy eating influence people’s intentions and motivations to eat unhealthily. Since these norms can be conveyed by one’s group in a manner that either promotes group members’ autonomy (i.e., collective autonomy support), or pressures them into eating certain foods (i.e., collective control), the experiment also tests which of these types of messages promotes the highest conformity to group norms. Hence, the second goal of this experiment was to investigate this synergetic effect of pro- vs anti-unhealthy eating norms and of collective autonomy support vs. collective control on participants’ unhealthy eating intentions and their motivations for unhealthy eating. An experimental study (N = 341) using a 2 (eating norm: pro-unhealthy eating norm vs. anti-unhealthy eating norm) x 3 (type of group support: collective autonomy support vs. collective control vs. no support) design was conducted. Results showed that pro-unhealthy eating norms increased participants’ intentions to eat salty and fatty food, but also their amotivation (i.e., lack of motivation) for unhealthy eating relative to anti-unhealthy eating norms. In addition, when pro-unhealthy eating was encouraged in a controlling (vs. in an autonomy supportive) manner, participants reported higher intentions to eat tofu tacos. Finally, when pro-unhealthy eating was promoted by supporting group members’ autonomy, participants reported higher integrated regulation, i.e., a highly internalized motivation, for unhealthy eating. These results demonstrate that eating norms do not impact all types of unhealthy food consumption in the same manner, and that collective control may be motivating in uncertain contexts; furthermore, when individuals’ autonomy is supported and promoted by other group members, they are more susceptible to integrate unhealthy eating in their life.

Perceptions of social norms around healthy and environmentally-friendly food choices: Linking the role of referent groups to behavior

Referent groups can moderate the perception of social norms and individuals’ likelihood to model these norms in food choice contexts, including vegetable intake and reduced meat consumption. The present study investigated whether having a close vs. a distant social group as the referent changed perceptions of social norms around making healthy and eco-friendly food choices. It also assessed whether these changes were associated with a difference in the health and environmental impacts of food choice in a virtual grocery shopping task. A nationally representative sample of UK adults (N = 2,488) reported their perceptions of making healthy and eco-friendly food choices being the norm among people they share meals with (close referent group) and most people in the UK (distant referent group). The former was more commonly perceived to be making both healthy (Z = −12.0, p &lt; 0.001) and eco-friendly (Z = −13.27, p &lt; 0.001) food choices than the latter. Perceptions of norms referring to the close group were significantly associated with the environmental (β = −0.90, 95% CIs: −1.49, −0.28) and health (β = −0.38 p &lt; 0.05, 95% CIs: −0.68, −0.08) impacts of participants’ food choices in a virtual shopping task. No such relationship was found for norms referring to the distant group for both environmental (β =0.43, p &gt; 0.05, 95% CIs: −1.12, 0.25) and health (β = −0.06, p &gt; 0.05, 95% CIs: −0.37, 0.25) impacts. Framing social norms around making healthy and eco-friendly food choices to refer to a close referent group may change their perceptions and ability to encourage sustainable and healthy food purchasing.

Optimizing an mHealth Intervention to Change Food Purchasing Behaviors for Cancer Prevention: Protocol for a Pilot Randomized Controlled Trial

BACKGROUND

Dietary intake is a powerful modifiable factor that influences cancer risk; however, most US adults do not adhere to dietary guidelines for cancer prevention. One promising pathway for improving dietary adherence is targeting grocery shopping habits. Interventions might facilitate healthy grocery choices, with a combination of mHealth and traditional methods, by promoting the salience of dietary goals while shopping, enhancing motivation to make dietary changes, and increasing household support for healthy food purchasing.

OBJECTIVE

This pilot study will assess feasibility and acceptability of intervention components designed to improve adherence to dietary guidelines for cancer prevention (preliminary aim). The primary aim of the study is to quantify the effect of each intervention component, individually and in combination, on dietary intake (primary aim) and grocery store food purchases (exploratory aim). Mediation analyses will be conducted to understand the mechanisms of action (goal salience, motivation, and household support-secondary aims). The overarching goal is to optimize an mHealth intervention to be tested in a future fully powered clinical trial.

METHODS

The study enrolled adults (N=62) with low adherence to dietary recommendations for cancer prevention. In a 20-week program, all participants attend a nutrition education workshop and receive weekly educational messages through an app. A factorial design is used to test 4 intervention components: (1) location-triggered messages: educational messages are delivered when arriving at grocery stores; (2) reflections on the benefits of change: content is added to messages to encourage reflection on anticipated benefits of healthy eating, and participants attend an additional workshop session and 3 coach calls on this topic; (3) coach monitoring: food purchases are monitored digitally by a coach who sends personalized weekly app messages and conducts 3 coaching calls that focus on feedback about purchases; and (4) household support: another adult in the household receives messages designed to elicit support for healthy food purchasing, and support is addressed in 3 coach calls and an extra workshop session attended by the index participant and household member. Assessments are completed at weeks 0, 10, and 20 using self-report measures, as well as objective capture of grocery data from the point of purchase using store loyalty accounts.

RESULTS

The National Cancer Institute funded this study (R21CA252933) on July 7, 2020. Participant recruitment began in the spring of 2021 and concluded with the successful enrollment of 62 participants. Data collection is expected to be completed in the summer of 2022, and results are expected to be disseminated in the summer of 2023.

CONCLUSIONS

The results of this study will inform the development of scalable interventions to lower cancer risk via changes in dietary intake.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04947150; https://clinicaltrials.gov/ct2/show/NCT04947150.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/39669.

A Social Norms and Identity Approach to Increasing Fruit and Vegetable Intake of Undergraduate Students in the United Kingdom

This study investigated the influence of descriptive norm messages that either communicated that university students eat a sufficient amount of fruit and vegetable (F&V) or that they do not, on F&V consumption, and whether or not any effects are moderated by student identification. An online 2 (Norm: "Sufficient"/"Insufficient") × 2 (Identification: "Low"/"High") experimental design was employed. Infographics containing "sufficient"/"insufficient" F&V intake descriptive norms were presented. An identification manipulation was employed to create "high"/"low" student identifiers. F&V intake intentions were assessed after the manipulations; self-reported F&V intake was reported at 2 days post-intervention. Undergraduate students in the United Kingdom (N = 180) reported their intake intentions, of which 112 (62%) completed the behavioral follow-up. Participants were predominantly white female students from Scottish universities, mean age 20.4 (±1.6) years. Baseline mean F&V consumption was high (4.5 ± 2.8). There were no significant main effects of Norm or Identification manipulations on F&V intentions and intake. Significant norm × identification interactions were revealed for fruit intake intentions and vegetable intake at follow-up, indicating half-portion differences (~40 g) between groups. Ironic effects were observed for "high" identifiers, who neither intended to, nor acted in accordance with group norms; "low" student identifiers intended to and followed group norms, whereby the "sufficient"/"low" group intended to consume significantly more fruit portions and consumed more vegetables than the "insufficient"/"low" group. Given the half-portion differences between groups resulting from the norm × identification interactions, future research on a larger sample of young adults with low F&V intake is warranted to further explore the conditions under which moderating effects of identification are observed and the underlying mechanisms.

Associations of clustered health risk behaviors with diabetes and hypertension in White, Black, Hispanic, and Asian American adults

Background

The clustering of Big Four contributors to morbidity and mortality—alcohol misuse, smoking, poor diet, and physical inactivity—may further elevate chronic health risk, but there is limited information about their specific combinations and associated health risks for racial/ethnic minority groups. We aimed to examine patterns of clustering in risk behaviors for White, Black, Hispanic, and Asian American adults and their associations with diabetes and hypertension. As these behaviors may be socioeconomically-patterned, we also examined associations between clustering and socioeconomic status (SES).

Methods

Latent class analyses and multinomial and logistic regressions were conducted using a nationally-representative sample of United States (US) adults ages 40–70 (N = 35,322) from Waves 2 (2004–2005) and 3 (2012–2013) of the National Epidemiologic Survey on Alcohol and Related Conditions. Obesity was used as a proxy for unhealthy diet. The outcomes were diabetes and hypertension.

Results

A relatively-healthy-lifestyle class was found only among White adults. Common patterns of unhealthy clustering were found across groups with some variations: the obese-inactive class among White, Black, and Hispanic adults (and the inactive class among Asian adults); the obese-inactive-smoking class among White, Black, and Hispanic adults; the smoking-risky-drinking class among White and Hispanic adults; and the smoking-risky-drinking-inactive class among Black and Asian adults. Positive associations of unhealthier clustering (having a greater number of risk behaviors) with lower SES (i.e., family income and education) and with health conditions were more consistent for Whites than for other groups. For racial minority groups, lower education than income was more consistently associated with unhealthy clusters. The associations between unhealthier clustering and diabetes and hypertension were less clear for Blacks and Asians than for Whites, with no significant association observed for Hispanics.

Conclusion

Concerted efforts to address clustered risk behaviors in most US adults, particularly in racial/ethnic minority groups given the high prevalence of unhealthy clustering, are warranted.

Policy framing, design and feedback can increase public support for costly food waste regulation

Stricter regulation of food waste reduction is widely presumed to increase food prices, which could render its implementation politically unfeasible. Here we empirically tested whether specific policy framing, design and feedback could help ensure public support despite potential food price increases. We used survey experiments with 3,329 citizens from a high-income country, Switzerland. A combined framing and conjoint experiment shows that messages emphasizing national or international social norms in favour of reducing food waste (policy framing) can increase public support for more ambitious reduction targets. Also, most citizens support food waste regulation even if this leads to substantial increases in food prices, but only if such policies set stringent reduction targets and are transparently monitored (policy design). Finally, a vignette experiment reveals that voluntary industry initiatives do not crowd out individuals' support for stricter governmental regulation, but potentially crowd in support if industry initiatives are unambitious (policy feedback).

Validity and Feasibility of the Monitoring and Modeling Family Eating Dynamics System to Automatically Detect In-field Family Eating Behavior: Observational Study

Background

The field of dietary assessment has a long history, marked by both controversies and advances. Emerging technologies may be a potential solution to address the limitations of self-report dietary assessment methods. The Monitoring and Modeling Family Eating Dynamics (M2FED) study uses wrist-worn smartwatches to automatically detect real-time eating activity in the field. The ecological momentary assessment (EMA) methodology was also used to confirm whether eating occurred (ie, ground truth) and to measure other contextual information, including positive and negative affect, hunger, satiety, mindful eating, and social context.

Objective

This study aims to report on participant compliance (feasibility) to the 2 distinct EMA protocols of the M2FED study (hourly time-triggered and eating event–triggered assessments) and on the performance (validity) of the smartwatch algorithm in automatically detecting eating events in a family-based study.

Methods

In all, 20 families (58 participants) participated in the 2-week, observational, M2FED study. All participants wore a smartwatch on their dominant hand and responded to time-triggered and eating event–triggered mobile questionnaires via EMA while at home. Compliance to EMA was calculated overall, for hourly time-triggered mobile questionnaires, and for eating event–triggered mobile questionnaires. The predictors of compliance were determined using a logistic regression model. The number of true and false positive eating events was calculated, as well as the precision of the smartwatch algorithm. The Mann-Whitney U test, Kruskal-Wallis test, and Spearman rank correlation were used to determine whether there were differences in the detection of eating events by participant age, gender, family role, and height.

Results

The overall compliance rate across the 20 deployments was 89.26% (3723/4171) for all EMAs, 89.7% (3328/3710) for time-triggered EMAs, and 85.7% (395/461) for eating event–triggered EMAs. Time of day (afternoon odds ratio [OR] 0.60, 95% CI 0.42-0.85; evening OR 0.53, 95% CI 0.38-0.74) and whether other family members had also answered an EMA (OR 2.07, 95% CI 1.66-2.58) were significant predictors of compliance to time-triggered EMAs. Weekend status (OR 2.40, 95% CI 1.25-4.91) and deployment day (OR 0.92, 95% CI 0.86-0.97) were significant predictors of compliance to eating event–triggered EMAs. Participants confirmed that 76.5% (302/395) of the detected events were true eating events (ie, true positives), and the precision was 0.77. The proportion of correctly detected eating events did not significantly differ by participant age, gender, family role, or height (P>.05).

Conclusions

This study demonstrates that EMA is a feasible tool to collect ground-truth eating activity and thus evaluate the performance of wearable sensors in the field. The combination of a wrist-worn smartwatch to automatically detect eating and a mobile device to capture ground-truth eating activity offers key advantages for the user and makes mobile health technologies more accessible to nonengineering behavioral researchers.

Food for teens: how social media is associated with adolescent eating outcomes

OBJECTIVE

To assess the relationship between exposure to social media food messages and self-reported adolescent eating outcomes (including food intake, perceived norms and food literacy).

DESIGN

A cross-sectional survey was used to assess reported exposure to core and non-core food messages (including marketing messages) on social media, as well as reported food intake, perceived norms, food literacy, attitudes, self-regulation, among others.

SETTING

18 secondary schools across Flanders, Belgium.

PARTICIPANTS

1002 adolescents 11-19 years of age.

RESULTS

Self-reported exposure to food marketing and overall food messages on social media was positively associated with eating attitudes, behaviours, perceived norms and food literacy among adolescents. Interestingly, the relationship between food exposure and intake was shaped differently depending on food type; descriptive norms mediated the positive relationship between non-core food social media exposure and non-core food intake (e.g. indirect effect estimate on self-reported sweets consumption is 0·005, se 0·002, P < 0·01), while food literacy mediated the positive relationship between core food social media exposure and core food intake (e.g. indirect effect estimate on self-reported vegetable consumption is 0·01, se 0·003, P < 0·000).

CONCLUSIONS

This study highlights the significance of social media in relation to adolescent eating. There is an opportunity for health professionals to use social media in the promotion of core food among adolescents. We call for relevant policy actions to regulate the marketing of non-core food to adolescents on social media.

Determinants of eating behaviour in Black, Asian and Minority Ethnic (BAME) university students when living at and away from home: With a focus on the influence of food enculturation and food acculturation

For some students, university, can be a period of increased autonomy in food choice and for black, Asian and minority ethnic (BAME) and international students, the addition of culture may be a governing factor. This study aimed to examine the extent of dietary acculturation and dietary enculturation on the influence of student's food choices using a phenomenological approach. Sixty participants (forty-one home students and nineteen international students) recruited by purposive sampling, were included in the study. Data collection involved self-administered multiple choice and short answer questionnaires and semi structured interviews. The results were analysed using thematic analysis. When living away from home, six major themes influenced the eating behaviour of the studied population: social environment, individual factors, physical environment, university life, enculturation and acculturation. When at home, five major themes were influential: social environment, individual factors, physical environment, enculturation and acculturation. The main findings suggest dietary enculturation is a factor which influences the dietary behaviour of both international students and BAME home students.

Digital Nudging for Online Food Choices

When people search for what to cook for the day, they increasingly use online recipe sites to find inspiration. Such recipe sites often show popular recipes to make it easier to find a suitable choice. However, these popular recipes are not always the healthiest options and can promote an unhealthy lifestyle. Our goal is to understand to what extent it is possible to steer the food selection of people through digital nudging. While nudges have been shown to affect humans' behavior regarding food choices in the physical world, there is little research on the impact of nudges on online food choices. Specifically, it is unclear how different nudges impact (i) the behavior of people, (ii) the time they need to make a decision, and (iii) their satisfaction and confidence with their selection. We investigate the effects of highlighting, defaults, social information, and warnings on the decision-making of online users through two consecutive user studies. Our results show that a hybrid nudge, which both involves setting a default and adding social information, significantly increases the likelihood that a nudged item is selected. Moreover, it may help decreasing the required decision time for participants while having no negative effects on the participant's satisfaction and confidence. Overall, our work provides evidence that nudges can be effective in this domain, but also that the type of a digital nudge matters. Therefore, different nudges should be evaluated in practical applications.

The influence of experimental confederate peers on children's food intake: A systematic review and meta-analysis

Confederates influence eating behaviour. Systematic reviews and meta-analyses have been conducted on this topic, however, the majority have examined adults, or a combination of adults and children, therefore, an up-to-date meta-analysis is needed to examine the impact of confederate peers on children's food intake. We systematically reviewed and meta-analysed the influence of confederate peers on children's food intake in research using present and remote-confederates. Six publications summarising findings from seven studies were included in this review. One publication was excluded from the meta-analysis because it was not possible to extract the required data. The meta-analysis showed that children were influenced by confederate peers; eating more when exposed to a high-intake compared to a no or low-intake confederate. Larger effects were observed when children were exposed to a remote-than a present-confederate, and for studies using healthy snacks compared to high fat high sugar (HFHS) snacks. No difference in effect size was observed when children were exposed to a high-vs. low-intake confederate compared to a high-vs. no-intake confederate. In the narrative synthesis, confederate intake influenced children's eating behaviour 24-h later, and possible moderators and a potential mechanism underlying the influence of confederates were identified. Caution is needed when interpreting the results, as the sub-groups were not compared statistically due to high heterogeneity, and a small number of studies were included in this review. Furthermore, all studies using the present-confederate design examined HFHS snack intake, therefore, it is unclear whether observed differences in effect sizes between present- and remote-confederates may be due to confederate or food type. Research is needed to further examine the influence of confederate peers on children's food intake and to examine mechanisms and moderators.

A dynamic social norm messaging intervention to reduce meat consumption: A randomized cross-over trial in retail store restaurants

Perceptions of social norms around eating behavior can influence food choices. Communicating information about how others are changing their eating behavior over time (dynamic descriptive social norms) may motivate individuals to change their own food selection and consumption. Following a four-week baseline period, 22 in-store restaurants of a major retail chain across the UK were randomized to display a dynamic descriptive social norm message intended to motivate a shift from meat-to plant-based meals either during the first two, or last two weeks of the four-week study period. A linear regression model showed there was no evidence of an effect of the intervention (β = -0.022, p = .978, 95% CIs: -1.63, 1.58) on the percentage sales of meat- vs plant-based dishes. Fidelity checks indicated that adherence to the intervention procedure was often low, with inconsistencies in the placement and display of the intervention message. In four stores with high fidelity the estimated impact of the intervention was not materially different. The lack of apparent effectiveness of the intervention may reflect poor efficacy of the intervention or limitations in its implementation in a complex food purchasing environment. The challenges highlighted by this study should be considered in future design and evaluation of field trials in real-world settings.

Reverse thinking: taking a healthy diet perspective towards food systems transformations

Food systems that deliver healthy diets without exceeding the planet’s resources are essential to achieve the worlds’ ambitious development goals. Healthy diets need to be safe, accessible, and affordable for all, including for disadvantaged and nutritionally vulnerable groups such as of smallholder producers, traders, and consumers in low- and middle-income countries. Globally, food systems are experiencing rapid and drastic changes and are failing to fulfil these multiple duties simultaneously. The international community therefore calls for rigorous food systems transformations and policy solutions to support the achievement of healthy diets for all. Most strategies, however, are essentially supply- and market-oriented. Incorporation of a healthy diet perspective in food system transformation is essential to enable food systems to deliver not only on supplying nutritious foods but also on ensuring that consumers have access can afford and desire healthy, sustainable, and culturally acceptable diets. This paper argues that this should be guided by information on diets, dietary trends, consumer motives, and food environment characteristics. Transformational approaches and policies should also take into account the stage of food system development requiring different strategies to ensure healthier diets for consumers. We review current knowledge on drivers of consumer choices at the individual and food environment level with special emphasis on low- and middle income countries, discuss the converging and conflicting objectives that exist among multiple food-system actors, and argue that failure to strengthen synergies and resolve trade-offs may lead to missed opportunities and benefits, or negative unintended consequences in food system outcomes. The paper proposes a menu of promising consumer- and food-environment- oriented policy options to include in the food systems transformation agenda in order to shift LMIC consumer demand towards healthier diets in low- and middle income countries.

Situating desire: Situational cues affect desire for food through eating simulations

How do situations influence food desire? Although eating typically occurs in rich background situations, research on food desire often focuses on the properties of foods and consumers, rather than on the situations in which eating takes place. Here, we take a grounded cognition perspective and suggest that a situation that is congruent with consuming a food increases simulations of eating it, which, in turn, affect desire, and the expected and actual liking of the food. We tested this idea in four pre-registered experiments (N = 524). Participants processed an image of a food presented in a congruent situation, an incongruent situation, or no background situation. Compared to the incongruent situation, the congruent situation increased expected liking of the food and desire, and this was partially or fully mediated by eating simulations. The congruent situation also increased salivation, a physiological indicator of preparing to eat. However, there was only weak and indirect evidence for congruence effects on actual liking of the food when tasted. These findings show that situational cues can affect desire for food through eating simulations. Thus, background situations play an important but understudied role in human food desires. We address implications for research using food images, and for applications to promote healthy and sustainable eating behaviour.

The role of perceived descriptive and injunctive norms on the self-reported frequency of meat and plant-based meal intake in UK-based adults

Perceived social norms refer to beliefs that people hold about what other people do (descriptive norms) and approve of (injunctive norms), and are associated with food intake. However, less is known about whether perceived social norms are associated with meat and plant-based meal intake. Using a cross-sectional survey design 136 participants (aged 19-66 years, mean age = 39.63, SD = 12.85 years, mean BMI = 25.77, SD = 5.30, 80.9 % female, 77.9 % omnivores, 22.1 % flexitarians) answered questions about how frequently they consumed meat and plant-based meals, and how frequently they perceived people in their social environment to consume (perceived descriptive norms), and approve of consuming (perceived injunctive norms) meat and plant-based meals. Perceived descriptive and injunctive norms were positively associated with participants' frequency of meat intake: participants ate meat more frequently when they perceived their significant other to frequently eat meat (descriptive norm), and when they perceived their significant other and friends to approve of (injunctive norm) frequently eating meat. Perceived descriptive norms were positively associated, but injunctive norms were negatively associated with participants' frequency of plant-based meal intake: participants ate plant-based meals more frequently when they perceived their extended family, friends, and significant other to frequently eat plant-based meals. However, participants ate plant-based meals more frequently when they perceived their extended family to approve of less frequent plant-based meal intake. These results suggest that different social groups may be important for meat and plant-based meal intake, with significant others and friends appearing to be important reference points for both food types. Further research examining the contexts in which the different social groups influence eating behaviour would be of value.

The social facilitation of eating: why does the mere presence of others cause an increase in energy intake?

There is strong evidence that people eat more when eating with friends and family, relative to when eating alone. This is known as the 'social facilitation of eating'. In this review, we discuss several gaps in the current scientific understanding of this phenomenon, and in doing so, highlight important areas for future research. In particular, we discuss the need for research to establish the longer-term consequences of social eating on energy balance and weight gain, and to examine whether people are aware of social facilitation effects on their own food intake. We also suggest that future research should aim to establish individual and contextual factors that moderate the social facilitation of eating (e.g. sex/gender), and it should clarify how eating socially causes people to eat more. Finally, we propose a novel evolutionary framework in which we suggest that the social facilitation of eating reflects a behavioural strategy that optimises the evolutionary fitness of individuals who share a common food resource.

Context matters: Self-regulation of healthy eating at different eating occasions

Self-regulation plays an important role in healthy eating behaviors. The current research explores temporary fluctuations in self-regulation next to variations between individuals. In an online observational study, 892 participants (M^age  = 44.3, SD^age  = 12.7) monitored their self-regulation three times a week before a meal moment for 3 weeks. To analyze the data, a random intercept and slopes model was used, including variables on within-individual level (i.e. meal moment, tiredness, distractedness, social, and physical environment) and variables on between-individual level (i.e. self-efficacy, intrinsic motivation, and perception of social and physical opportunity). Self-regulation was found to be higher at breakfast compared with dinner (estimate = -0.08, p < .001), higher at home than out-of-home (estimate = -0.08, p < .001) and lower when individuals are more tired (estimate = 0.04, p < .001) and distracted (estimate = 0.07, p < .001). Moreover, self-regulation was higher for individuals with higher levels of intrinsic motivation (estimate = 0.19, p < .001) and self-efficacy (estimate = 0.41, p < .001). Insights from this research advance our knowledge regarding temporal influences on self-regulation and can provide input for behavior change tools such as personalized dietary advice.

Intake of Antioxidant Vitamins and Minerals in Relation to Body Composition, Skin Hydration and Lubrication in Young Women

The aim of this study was to estimate the consumption of selected dietary components with antioxidant properties, undertake body composition analysis, assess skin hydration and lubrication, and establish the relationships between the above parameters. The study was carried out on 172 young women. The consumption of ingredients (vitamins A, C, D and E, and Cu, Mn, Zn) was assessed using the Diet 6.0 program, body composition was assessed using electrical bioimpedance and skin hydration and lubrication were assessed using the corneometric and sebumetric methods, respectively. About one-third of students showed insufficient consumption of vitamin C, vitamin E and zinc, while about 99% showed insufficient vitamin D levels. The highest degree of hydration was observed in the areas of the eyelids, neckline and chin. The greatest amount of sebum was found in the area of the nose and forehead. Low positive correlations between hydration or lubrication and Cu, vitamin A and vitamin E were observed. In conclusion, to properly moisturize and lubricate the skin, young women should eat products that are rich in ingredients with antioxidant properties, in particular fat-soluble vitamins A and E, but also copper.

What Is Commensality? A Critical Discussion of an Expanding Research Field

Commensality (the act of eating together) is studied in a range of disciplines and often considered important for social communion, order, health and well-being, while simultaneously being understood as in decline (especially the family meal). However, such claims are also contested in various ways. In this paper, we discuss the expanding field of commensality research and critically reflect on the debates surrounding its social functions, including its role in public health. We illuminate the deep social and cultural significance of commensality, through time and space, and conclude that whether or not commensality is the preferred social form of eating for any given individual, it is difficult to escape its sociocultural desirability and idealization. As a cross-cultural phenomenon in both past, present, and future, we suggest that commensality deserves further research. This includes commensality as a research topic in itself and as an entry point to unveil different dimensions of social relations between people, as well as interactions between humans and material objects.

Challenging the Status Quo through Social Influence: Changes in Sustainable Consumption through the Influence of Social Networks

This study examines the influence of social network members (versus strangers) on sustainable food consumption choices to investigate how social influence can challenge the status quo in unsustainable consumption practices. We hypothesized that changes to individual consumption practices could be achieved by revealing ‘invisible’ descriptive and injunctive social norms. We further hypothesized that it matters who reveals these norms, meaning that social network members expressing their norms will have a stronger influence on other’s consumption choices than if these norms are expressed by strangers. We tested these hypotheses in a field experiment (N = 134), where participants discussed previous sustainable food consumption (revealing descriptive norms) and its importance (revealing injunctive norms) with either a stranger or social network member. We measured actual sustainable food consumption through the extent to which participants chose organic over non-organic consumables during the debrief. Findings showed that revealed injunctive norms significantly influenced food consumption, more so than revealed descriptive norms. We also found that this influence was stronger for social network members compared to strangers. Implications and further research directions in relation to how social networks can be used to evoke sustainable social change are discussed.

A randomised experiment of health, cost and social norm message frames to encourage acceptance of swaps in a simulation online supermarket

Offering lower-energy food swaps to customers of online supermarkets could help to decrease energy (kcal) purchased and consumed. However, acceptance rates of such food swaps tend to be low. This study aimed to see whether framing lower-energy food swaps in terms of cost savings or social norms could improve likelihood of acceptance relative to framing swaps in terms of health benefits. Participants (n = 900) were asked to shop from a 12-item shopping list in a simulation online supermarket. When a target high-energy food was identified in the shopping basket at check-out, one or two lower-energy foods would be suggested as an alternative (a “swap”). Participants were randomised to only see messages emphasising health benefits (fewer calories), cost benefits (lower price) or social norms (others preferred this product). Data were analysed for 713 participants after exclusions. Participants were offered a mean of 3.17 swaps (SD = 1.50), and 12.91% of swaps were accepted (health = 14.31%, cost = 11.49%, social norms = 13.18%). Swap acceptance was not influenced by the specific swap frame used (all p > .170). Age was significantly and positively associated with swap acceptance (b = 0.02, SE = 0.00, p < .001), but was also associated with smaller decreases in energy change (b = 0.46, SE = .19, p = .014). Overall, offering swaps reduced both energy (kcal) per product (b = -9.69, SE = 4.07, p = .017) and energy (kcal) per shopping basket (t₇₁₂ = 11.09, p < .001) from pre- to post-intervention. Offering lower-energy food swaps could be a successful strategy for reducing energy purchased by customers of online supermarkets. Future research should explore alternative solutions for increasing acceptance rates of such swaps.

Nudging Consumers toward Healthier Food Choices: A Field Study on the Effect of Social Norms

Food choices influence the health of individuals, and supermarkets are the place where part of the world population makes their food choices on a daily basis. Different methods to influence food purchasing habits are used, from promotions to food location. However, very few supermarket chains use social norms, the human need to conform to the perceived behavior of the group, to increase healthy food purchase habits. This research seeks to understand how a social norm nudge, a message conveying fruit and vegetable purchasing norms positioned in strategic places, can effectively change food choices. Using data from an intervention in a Portuguese supermarket, the fruit and vegetable purchase quantities of 1636 customers were measured over three months and compared with the corresponding period of the previous year. The results show that the nudge intervention positively affected those whose purchasing habits are categorized as less healthy, while those with healthy habits were slightly negatively affected. Moreover, a follow-up inferential statistical analysis allows us to conclude that applying this intervention at a larger scale would deliver significant financial results for the supermarket chain in which the study took place, by decreasing the costs related to produce perishability while simultaneously improving the health of the consumer and the sustainability of the planet.