A social network-based intervention stimulating peer influence on children's self-reported water consumption: A randomized control trial

Examining the New Zealand school food environment: what needs to change?

Habitual dietary intakes and nutrition behaviours developed during childhood and adolescence pave the way for similar behaviours to manifest in adulthood. Childhood obesity rates have now reached a point where one in six children globally are classified as overweight or obese. Schools have the unique ability to reach almost all children during key developmental stages, making them an ideal setting for influencing children's nutrition behaviours. Evidence suggests the school food environment is not always conducive to healthy food choices and may be obesogenic. The aim of this narrative review is to explore factors that influence the healthy food and drink environment in and around schools in New Zealand. The review focused on evidence from New Zealand and Australia given the close resemblance in education systems and school food guidance. Using the Analysis Grid for Environments Linked to Obesity (ANGELO) framework, the school food environment was categorised into the following domains: economic, political, physical and socio-cultural factors. Findings suggest that food policies are not utilised within schools, and guidelines to improve the school food environment are not well implemented. Canteen profit models, lack of staff support and resources, and higher availability of low-cost unhealthy foods are among barriers that hinder implementation. This review highlights recommendations from existing evidence, including canteen pricing strategies, restriction of unhealthy foods and using peer modelling in a time-scarce curriculum to improve the school food environment. Key areas for improvement, opportunities to enhance policy implementation and untapped avenues to improve the food and nutrition behaviours of children are highlighted.

Thirsty? Choose Water! A regional perspective to promoting water consumption in secondary school students

OBJECTIVE

Adolescents are high consumers of sugar-sweetened beverages (SSB), which contribute to overweight and obesity - a significant public health issue. Evidence suggests that replacing SSB with water and school-based interventions can reduce consumption. This study examines the acceptability of a previously trialled intervention (Thirsty? Choose Water!) in regional and remote secondary schools.

DESIGN

An open-label randomised controlled trial using a two-by-two factorial design tested the outcomes of a behavioural and/or environmental intervention on SSB and water consumption.

SETTING

Regional and remote secondary schools (public, catholic and independent) within the boundaries of two regional Local Health Districts within New South Wales.

PARTICIPANTS

Twenty-four schools participated in the study. The target group was year 7 students (n 1640) - 72 % of eligible students completed baseline data. The study followed students into year 8 (n 1188) - 52 % of eligible students completed post-intervention data. Forty teachers undertook training to deliver the intervention.

RESULTS

Interventions showed high levels of acceptability. Students demonstrated changes in knowledge, attitudes and consumption behaviours. Multivariable ordinal logression analysis demonstrated that all interventions increased the odds of students increasing their water consumption (though not statistically significant). Conversely, the combined (OR: 0·75; 95 % CI: 0·59, 0·97) or environmental intervention (OR: 0·68; 95 % CI: 0·51, 0·90) had greater odds of reducing SSB consumption and was statistically significant.

CONCLUSIONS

This study builds on recent Australian evidence regarding the impact of school-based interventions on water and SSB consumption. In this study, despite a minor intervention change, and the impacts of fires, floods and COVID-19 on study implementation, the interventions were highly regarded by the school communities with positive outcomes.

Bringing down barriers to children's healthy eating: a critical review of opportunities, within a complex food system

This narrative review revises the scientific evidence of recent years on healthy eating in children and adolescents, making sense of promising avenues of action, from a food system perspective. A conceptual framework is provided to better understand how eating habits of children and adolescents are shaped to identify key multisectoral approaches that should be implemented to promote healthier diets. The following influencing factors are discussed: individual factors (physiological and psychological factors, food preferences and food literacy competencies), factors within the personal and socio-cultural food environments, external food environments, and the supply chain. In each section, the main barriers to healthy eating are briefly discussed focussing on how to overcome them. Finally, a discussion with recommendations of actions is provided, anchored in scientific knowledge, and transferable to the general public, industry, and policymakers. We highlight that multidisciplinary approaches are not enough, a systems approach, with a truly holistic view, is needed. Apart from introducing systemic changes, a variety of interventions can be implemented at different levels to foster healthier diets in children through fostering healthier and more sustainable food environments, facilitating pleasurable sensory experiences, increasing their food literacy, and enhancing their agency by empowering them to make better food related decisions. Acknowledging children as unique individuals is required, through interpersonal interactions, as well as their role in their environments. Actions should aim to enable children and adolescents as active participants within sustainable food systems, to support healthier dietary behaviours that can be sustained throughout life, impacting health at a societal level.

The effect of a multi-component school-based social network intervention on children's body mass index: a four-arm intervention study

Objective: Schools are considered an important setting for stimulating healthy weight. The current study is unique in examining effects of a multi-component school-based social network intervention on children's body mass index z-scores (zBMI).Methods: Four schools were randomly allocated to one of four conditions: a social network intervention using influence agents focusing on water consumption, physical activity, a combination of the two, or a passive control condition. Participants included a total of 201 6- to-11-year-old children (53.7% girls; Mage = 8.51, SDage = 0.93). At baseline, 149 (76.0%) participants had a healthy weight, 29 (14.8%) had overweight and 18 (9.2%) had obesity.Results: Linear mixed effect models indicated that a multi-component school-based social network intervention targeting both water consumption and physical activity was most effective in decreasing children's zBMI.Conclusion: This study suggests that schools can contribute to the intervention of childhood obesity-even without involving the parents-by targeting both children's water consumption and physical activity through influential peers, but more research is needed to identify mechanisms of change.

Prospective association of family members' sugar-sweetened beverages intake with children's sugar-sweetened beverages consumption in China

PURPOSE

We aimed to investigate whether parental and siblings' sugar-sweetened beverage (SSB) intake had prospective impact on children's SSB consumption, and the potential sex difference in these associations.

METHODS

This study included a total of 904 children and their parents enrolled from 2004 to 2011 China Health and Nutrition Survey (CHNS) cohort study. SSB consumption information was estimated using a short dietary questionnaire and total energy intake was assessed with three-day 24-h dietary assessments at recruitment and follow-up surveys. Multivariate logistic or linear regression analyses were used to assess the association for SSB consumption between parents, siblings and children after adjusting for age, body mass index (BMI) z-score, household income and parental educational level.

RESULTS

In this study, a majority (87.6%) of children consumed SSB. Among them, the median consumption of SSB was 70.3 ml/day per capita and 205.4 ml/day per consumer. Parental SSB consumption was relevant to children's SSB consumption, and this association was more pronounced in boys than in girls. Meanwhile, fathers seemed to have a stronger impact on whether children consume SSB than mothers which was reflected by lower P and higher OR. Additionally, children's SSB intake was prospectively associated with their older siblings' SSB consumption (P _{for trend} < 0.03).

CONCLUSIONS

Parental and older siblings' SSB consumption was relevant to children's SSB intake. Particularly, boys were more susceptible to parental impact than girls, and fathers seemed to have a greater influence on children than mothers.

A systematic review and meta-analysis of the benefits of school-based, peer-led interventions for leaders

The aim of our systematic review and meta-analysis was to quantitatively synthesise the effects of school-based peer-led interventions on leaders' academic, psychosocial, behavioural, and physical outcomes. Eligible studies were those that: (i) evaluated a school-based peer-led intervention using an experimental or quasi-experimental study design, (ii) included an age-matched control or comparison group, and (iii) evaluated the impact of the intervention on one or more leader outcomes. Medline, Sportdiscus, Psychinfo, Embase, and Scopus online databases were searched on the 24th of October, 2022 which yielded 13,572 results, with 31 included in the narrative synthesis and 12 in the meta-analysis. We found large positive effects for leaders' attitudes toward bullying (d = 1.02), small-to-medium positive effects for leaders' literacy (d = 0.39), and small positive effects for leaders' self-esteem (d = 0.18). There were mixed findings for behavioural outcomes and null effects for physical outcomes. Notable limitations of this research are the inclusion of a relatively small number of studies, and high heterogeneity in those included. Our findings have the potential to inform educational practice, but also highlight the need for further research examining the mechanisms that might account for the observed effects. Our systematic review was prospectively registered with PROSPERO (CRD42021273129).

'I Knew I Should Stop, but I Couldn't Control Myself': a qualitative study to explore the factors influencing adolescents' consumption of sugar-sweetened beverages and sugary snacks from a socio-ecological perspective

OBJECTIVE

To explore the factors influencing Taiwanese adolescents' consumption of sugar-sweetened beverages (SSB) and sugary snacks from a socio-ecological perspective.

DESIGN

This study adopted a qualitative design by using face-to-face, in-depth interviews guided by a semistructured questionnaire.

SETTING

Eight junior high schools in New Taipei City and Changhua County, Taiwan, September to November 2018.

PARTICIPANTS

Fifty-nine participants aged 12-14 years participated in this study.

RESULTS

Reflexive thematic analysis was used to analyse the data. This study identified four themes to address the multifaceted factors that influence adolescents' consumption of SSB and sugary snacks. At the intrapersonal level, physiological factors, psychological factors, individual economic factors and taste preferences were mentioned in connection with people's consumption of SSB and sugary snacks. Positive or negative influences of parents, siblings, peers and teachers on SSB and sugary snack intake were identified at the interpersonal level. The availability of SSB and sugary snacks at home, their availability in vending machines or in school stores in the school environment and participants' access to convenience stores and hand-shaken drink shops in the broader community influenced SSB and sugary snack consumption. Additionally, food culture and food advertising were identified as influencing societal factors.

CONCLUSIONS

Overall, this qualitative study determined not only that the consumption of SSB and sugary snacks is influenced by intrapersonal factors but also that interpersonal, environmental and societal factors affect adolescents' increased sugar intake. The findings are helpful to broaden the options for designing and developing interventions to decrease SSB and sugary snack consumption by adolescents.

Motivating Social Influencers to Engage in Health Behavior Interventions

Social influencers are widely known as the promotors of purchase behavior as well as for their potential to change health behaviors among individuals in their social networks. For social influencers to be successful in changing behaviors, it is essential that they convey their message in an authentic, original, credible, and persistent manner. In the context of health behavior interventions, this requires a focus on the motivation of social influencers to engage in the intervention. This perspective article describes the importance of motivating social influencers to engage in the desired health behaviors themselves and to promote it within their social network. We briefly describe the current state of knowledge and our empirical experience in implementing health interventions with social influencers. Using insights from self-determination theory, we demonstrate how social influencers can be motivated optimally in health behavior interventions and, thereby, improving the success of the intervention. To illustrate these insights and guide intervention practice, we provide concrete examples of techniques that can be applied in health interventions involving social influencers. We conclude with directions for further research and intervention practice to improve the delivery of health behavior interventions.

The Influence of a School Social Network Intervention on Adolescent's Health Behaviors: A Gender-Specific Agent-Based Model

Introduction

Adolescence is a crucial stage for health behavior development, which is associated with health in adulthood. School closures caused by the coronavirus disease 2019 (COVID-19) pandemic have exposed adolescents to an increased risk of obesity due to a lack of physical activity. Although social network interventions provide an effective approach for promoting health-related behavior, current practices neglect gender differences in adolescent behavioral patterns and emotional preferences. The aim of this study was to examine the effectiveness of centrality-based methods integrated with of gender contexts in a social network intervention to improve adolescent's health behavior.

Methods

We developed an agent-based model (ABM) that supports the small-world characteristics of adolescent social networks. Health-related data for junior middle school students (n = 234, 48% girls) were collected in November 2018, 2019 and 2020 in Tianjin, China. We simulated multiple network-based interventions with different criteria for influential agents (i.e., betweenness centrality, closeness centrality, eigenvector centrality, and PageRank) and a random condition. The rules for generating peer influence and accelerating behavioral changes were based on the diffusion of innovations theory, with gender specifications.

Results

After the school closures, there was a significant increase in the prevalence of overweight and obesity among adolescents, with a greater increase in girls than in boys (+8.85% vs. +1.65%, p < 0.001). Simulations showed that centrality-based network interventions were more effective than the random condition (average 6.17% per tick vs. 5.22% per tick, p < 0.05), with a higher efficiency in girls than boys (average 3.68% vs. 2.99% per tick, p < 0.05). PageRank outperformed other centrality conditions at the population level (6.37% per tick, p < 0.05). In girls, betweenness centrality was the best method (3.85% per tick, p < 0.05), while in boys, PageRank still had the greatest efficiency (3.21% per tick, p < 0.05).

Conclusions

We found evidence for gender differences in the negative impact of COVID-19-related school closures and the potential for centrality-based social network interventions to affect adolescent health behavior. Therefore, we emphasize the importance of gender-specific targeting strategies to further promote health-related school programs in the post-pandemic era.

Evaluation of the 'H2NOE Water Schools' programme to promote water consumption in elementary school children - a non-randomised controlled cluster trial

Objective:

This study evaluated a simple environmental intervention called ‘Water Schools’ in Lower Austria providing free refillable water bottles and educational material.

Design:

Non-randomised controlled cluster trial with three measurements: at baseline (T0), after the intervention at 9 months (T1) and after 1-year follow-up (T2).

Setting:

Half-day elementary schools in Lower Austria (Austria).

Participants:

Third-grade pupils from twenty-two schools in the intervention group (IG) and thirty-two schools in the control group (CG) participated in the study. Data were analysed for 569 to 598 pupils in the IG and for 545 to 613 in the CG, depending on the time of measurement.

Results:

The consumption of tap water increased in the IG from baseline to T1 and then decreased again at T2, but this was similar in the CG (no statistically significant difference in the time trend between the IG and CG). Similar results were seen for tap water consumption in the mornings. The proportion of children who only drank tap water on school mornings increased significantly from baseline to T1 in the IG compared to the CG (P = 0·020). No difference in the changes over time occurred between the groups for the proportion of pupils drinking approximately one bottle of tap water during school mornings.

Conclusions:

Not only the children in the IG but also those in the CG drank more tap water after 1 school year than at the beginning. The measurement of drinking habits in the CG may have been intervention enough to bring about changes or to initiate projects.

Themes in Train-the-Trainer Nutrition Education Interventions Targeting Middle School Students: A Systematic Review

Context-appropriate nutrition education interventions targeting middle school students have the potential to promote healthy dietary patters that may help prevent unnecessary weight gain at a point in childhood development when youth experience increasing agency over their food choices. The aim of this review was to identify and synthesize themes in train-the-trainer approaches, intervention content and delivery, and youth receptivity across teacher, mentor, and peer-led nutrition education interventions that targeted middle school-age youth in urban, primarily low-income settings. A systematic, electronic literature search was conducted in seven electronic databases, PubMed/Medline, CINAHL, ERIC, PsycINFO, Scopus, SPORTDiscus, and Cochrane CENTRAL, using fixed inclusion and exclusion criteria. A total of 53 papers representing 39 unique interventions were selected for data extraction and quality assessment. A framework synthesis approach was used to organize the interventions into six categories and identify themes according to whether the intervention was classroom-based or out-of-school-based and whether adults, cross-age peers or same-age peers delivered the intervention. Ten of the interventions contained multiple components such that they were included in two of the categories. The review findings indicated that trainings should be interactive, include opportunities to role-play intervention scenarios and provide follow-up support throughout intervention delivery. Interventions targeting middle school youth should include positive messaging and empower youth to make healthy choices within their specific food environment context.

Sugar-Sweetened Beverage Consumption, Perceptions, and Disparities in Children and Adolescents

OBJECTIVE

To examine the association between sugar-sweetened beverage (SSB) perceptions-knowledge, attitudes, and norms and media literacy-and beverage consumption, and to identify differences in beverage consumption and SSB perceptions by race/ethnicity and socioeconomic status.

DESIGN

Cross-sectional.

SETTING

Diverse California school district.

PARTICIPANTS

A total of 992 fifth-grade (elementary), seventh-grade (middle), and ninth-12th-grade (high school) students.

MAIN OUTCOME MEASURES

Questionnaire-assessed continuous beverage consumption and perceptions.

ANALYSIS

Linear regression adjusting for school, grade, gender, race/ethnicity, and free and reduced-price meal (FRPM) eligibility.

RESULTS

Knowledge, attitudes, and norms, and media literacy items were associated with SSB consumption in expected directions (P < 0.05). Among elementary students, FRPM-eligible and Black students had higher SSB consumption (P < 0.01). In middle/high school, non-Hispanic White students consumed fewer SSBs than all other racial/ethnic groups (P < 0.01). There were differences in SSB-related perceptions by race/ethnicity and socioeconomic status (eg, Black students perceived sugary drinks as less unhealthy); Black, Hispanic, and FRPM-eligible students expressed less distrust of food/beverage advertisements; and Black, Hispanic, Asian, multirace, and FRPM-eligible students perceived more frequent SSB consumption among their peers (P < 0.05).

CONCLUSIONS AND IMPLICATIONS

Sugar-sweetened beverage perceptions were associated with SSB consumption. There were racial/ethnic and socioeconomic disparities in SSB consumption and perceptions. Sugar-sweetened beverage perceptions and related social and commercial determinants like marketing may be useful targets for reducing SSB consumption.

Promoting water consumption among Dutch children: an evaluation of the social network intervention Share H2O

Background

There is a need to develop and improve interventions promoting healthy drinking behaviors among children. A promising method could be to stimulate peer influence within children’s social networks. In the Share H₂O social network intervention (SNI), peer influence was utilized by selecting a subset of influential children and training them as ‘influence agents’ to promote water consumption—as an alternative to SSBs. Previous research has mainly focused on the process of selecting influence agents. However, the process of motivating influence agents to promote the behavior has hardly received any research attention. Therefore, in the SNI Share H₂O SNI, this motivation process was emphasized and grounded in the self-determination theory (SDT). This study evaluated the implementation of the Share H₂O SNI, focusing on whether and how applying SDT-based techniques can motivate the influence agents and, indirectly, their peers.

Methods

This study included data collected in the Netherlands from both the influence agents (n = 37) and the peers (n = 112) in the classroom networks of the influence agents.

Self-reported measurements assessed the influence agents’ enjoyment of the training, duration and perceived autonomy support during the training, and changes in their intrinsic motivation and water consumption before and after the start of the intervention. Changes in the peers’ intrinsic motivation, perceived social support, and social norms were measured before and after the start of the intervention.

Results

The influence agents enjoyed the training, the duration was adequate, and perceived it as autonomy supportive. There was an increase in the influence agents’ intrinsic motivation to drink water and their actual water consumption. Providing personal meaningful rationales seemed to have motivated the influence agents. The intrinsic motivation and perceived descriptive norm of the peers remained stable. The peers reported an increase in their perceived social support and injunctive norm concerning water drinking after the intervention. Influence agents appeared to mainly use face-to-face strategies, such as modeling, talking to peers, and providing social support to promote the behavior.

Conclusions

The current findings provided preliminary evidence of the promising effects of using SDT-based techniques in an SNI to motivate the influence agents and, indirectly, their peers.

Trial registration

NTR, NL6905, Registered 9 January 2018, https://www.trialregister.nl/trial/6905

Promoting water consumption among children: a three-arm cluster randomised controlled trial testing a social network intervention

Objective:

To test the effectiveness of a social network intervention (SNI) to improve children’s healthy drinking behaviours.

Design:

A three-arm cluster randomised control trial design was used. In the SNI, a subset of children were selected and trained as ‘influence agents’ to promote water consumption–as an alternative to sugar-sweetened beverages (SSB)–among their peers. In the active control condition, all children were simultaneously exposed to the benefits of water consumption. The control condition received no intervention.

Setting:

Eleven schools in the Netherlands.

Participants:

Four hundred and fifty-one children (M_age = 10·74, SD_age = 0·97; 50·8 % girls).

Results:

Structural path models showed that children exposed to the SNI consumed 0·20 less SSB per day compared to those in the control condition (β = 0·25, P = 0·035). There was a trend showing that children exposed to the SNI consumed 0·17 less SSB per day than those in the active control condition (β = 0·20, P = 0·061). No differences were found between conditions for water consumption. However, the moderation effects of descriptive norms (β = –0·12, P = 0·028) and injunctive norms (β = 0·11–0·14, both P = 0·050) indicated that norms are more strongly linked to water consumption in the SNI condition compared to the active control and control conditions.

Conclusions:

These findings suggest that a SNI promoting healthy drinking behaviours may prevent children from consuming more SSB. Moreover, for water consumption, the prevailing social norms in the context play an important role in mitigating the effectiveness of the SNI.

Promoting healthy foods in the new digital era on Instagram: an experimental study on the effect of a popular real versus fictitious fit influencer on brand attitude and purchase intentions

Background

Most studies on social influencer marketing techniques have focused on the promotion of unhealthy foods whereas little is known about the promotion of healthier foods. The present experimental study investigated whether a popular real versus fictitious fit influencer is more successful in promoting healthy food products. In addition, we examined the role of parasocial interaction as an underlying mechanism of healthy food product endorsement.

Methods

We used a randomized between-subject design with 154 participants (mean age: 24.0 years). Viewers’ product attitude and purchase intention were tested after exposure to an Instagram post by a popular real fit influencer (n = 77) or fictitious fit influencer (n = 77).

Results

Results showed that parasocial interaction mediated the relation between the type of influencer and product attitude as well as purchase intention. Parasocial interaction was higher for participants exposed to the popular real fit influencer compared to the fictitious fit influencer, leading to higher healthy food brand attitude and purchase intention.

Discussion

The findings showed that it is crucial for social influencers to establish a warm personal relationship and connection with the their followers when promoting a healthy product successfully. We suggest that the promotion of healthy foods could be more successful in public health when using popular fit influencers.

Preadolescents' healthy eating behavior: peeping through the social norms approach

BACKGROUND

The rising childhood obesity rate is a major public health challenge. The objective of this study is to examine key underlying mechanisms for peer-related social influence on preadolescents' healthy eating behavior by including factors closely linked with the quality of preadolescents' relationship with peers.

METHODS

A cross-sectional study was conducted in a convenience sample of 278 Lithuanian preadolescents, recruited from a public school. A questionnaire containing sociodemographic questions, questions about food intake, peer-related social norms of healthy eating, social self-efficacy, vegetable preference, need for peer approval and feeling of belonging were applied. Data was analyzed using structural equation modeling.

RESULTS

The results of the SEM showed that social self-efficacy predicts feeling of belonging to the peer group and need for peer approval. Feeling of belonging and need for peer approval predict actual intake of vegetables via injunctive norms of healthy eating. However, neither feeling of belonging nor need for peer approval predicted descriptive norms of healthy eating. Contrary to our expectations, descriptive norms were found to be unrelated with actual intake of vegetables, though vegetable preference predicted actual intake of vegetables. Vegetable preference was not predicted by injunctive or descriptive peers' social norms of healthy eating.

CONCLUSIONS

The findings of this study offer insight for informing parents, teachers and for social norms marketing interventions by stressing the importance of social relations when the aim is to encourage healthy eating among preadolescents.

Experts, peers, or celebrities? The role of different social endorsers on children's fruit choice

This study investigates whether the source providing nutritional information matters for children's choice of fruit over candy. We conducted a between-subject experimental study with children (6-11 years; M_age = 8.20; N = 340). Children watched an audiovisual cartoon with nutritional messages provided by experts (expert condition), by celebrities (celebrity condition), or by typical consumers (peer condition). Additionally, we included a control group in which children were not exposed to any cartoon. As the dependent variable, we measured children's fruit choice over candy. As a mediator, measuring message processing we included children's argument awareness. Children's age was included as a moderator. The results indicate that the experimental conditions were equally effective in creating argument awareness for healthy eating compared to the control group. Children's argument awareness was generally rather low, and it did not influence children's fruit choice over candy. Nevertheless, there was a direct effect of the expert condition on children's fruit choice, pointing to an internalized "expert heuristic". No moderating effects of children's age were present. Our study indicates that using experts to present nutritional information within narrative media content is a potentially successful strategy to create argument awareness for healthy food and to impact children's selection of healthy food whereas peer and celebrity social endorsers are not.

Interventions to increase the consumption of water among children: A systematic review and meta-analysis

The aim of this study was to conduct a systematic review and meta-analysis on the effectiveness of interventions to increase children's water consumption. A systematic literature search was conducted in seven electronic databases. Studies published in English before 18 February 2019 that evaluated any type of intervention that measured change in water consumption among children aged 2 to 12 years by applying any type of design were included. Of the 47 interventions included in the systematic review, 24 reported a statistically significant increase in water consumption. Twenty-four interventions (17 randomized controlled trials and seven studies with other controlled designs) were included in the meta-analysis. On average, children in intervention groups consumed 29 mL/d (confidence interval [CI] = 13-46 mL/d) more water than did children in control groups. This effect was larger in eight interventions focused specifically on diet (MD = 73 mL/d, CI = 20-126 mL/d) than in 16 interventions focused also on other lifestyle factors (MD = 15 mL/d, CI = 1-29 mL/d). Significant subgroup differences were also found by study setting and socioecological level targeted but not by children's age group, intervention strategy, or study design. In conclusion, there is evidence that, on average, lifestyle interventions can lead to small increases in children's daily water consumption. More research is needed to further understand the specific intervention elements that have the greatest effect.

Exploring the directionality in the relationship between descriptive and injunctive parental and peer norms and snacking behavior in a three-year-cross-lagged study

Background

People’s eating behavior is assumed to be influenced by what other people do (perceived descriptive norms) and what others approve of (perceived injunctive norms). It has been suggested that adolescents are more susceptible to peer norms than parental norms, because they experience a strong need for group acceptance that leads to conforming to peer group norms. The current study examined changes in snacking behavior and four types of social norms (i.e., parental and peer descriptive and injunctive norms) that promoted fruit and vegetable intake among adolescents. This study was the first to examine whether snacking behavior also influenced norm perceptions by testing the directionality of these associations.

Methods

The study consisted of 819 participants (M [SD] age = 11.19 [1.36]; 46.1% boys), collected at three time points (T1 = 2016, T2 = 2017 and T3 = 2018) during the MyMovez project. Self-reported frequency of snack consumption, perceived parental and peer descriptive and injunctive norms were assessed. The primary analysis consisted of a series of cross-lagged autoregressive models specified in a structural equation modeling framework.

Results

Model comparisons testing the descriptive and injunctive norms in separate models and in an additional combined model revealed evidence for bi-directional associations between norms and snacking behavior. Descriptive peer and parent norms were not found to have an effect on subsequent snacking behaviors. Perceived injunctive parental norms were positively associated with healthy snack food intake and negatively associated with unhealthy snack intake (forward direction). Injunctive peer norms were negatively associated with healthy snack food intake. In addition, higher unhealthy snack food intake was negatively associated with the perception of descriptive and injunctive parental norms 1 year later (reversed direction). We did not find peer norms to be more closely associated with changes in snacking behaviors compared to parental norms.

Conclusions

Parents expecting their children to snack healthy had a positive influence on healthy snacking behavior whereas only acting as a healthy role model did not. Future research should address the possible interaction between descriptive and injunctive norms. Research should also take into account the bi-directional relations between eating behaviors and normative perceptions.

Correlates of sugar-sweetened beverages consumption among adolescents

Objective:

To identify correlates and underlying beliefs regarding the adolescents’ intention to abstain from consuming sugar-sweetened beverages (SSB) and the consumption of ≤1 daily portion of SSB.

Design:

Correlational study.

Setting:

Region of Chaudière-Appalaches in the province of Quebec, Canada.

Participants:

311 adolescents aged 13–18 years completed a self-administrated online questionnaire based on the Reasoned Action Approach. Frequency and quantity of different types of SSB within the past month were measured.

Results:

Total mean SSB intake was 882·6 ml/d (654·0 kJ/d ). Only 11·3 % abstained from SSB within the last month. Intention to abstain from SSB was explained by identification as SSB abstainers (β = 0·47), perceived norm (β = 0·32), attitude (β = 0·30), age 13–14 years (β = –0·27) and perception of the school environment (β = 0·14), which explained 66 % of the variance. Consumption of ≤1 daily portion of SSB was explained by the intention to abstain (OR = 1·55; 95 % CI 1·14, 2·11), perceived behavioural control to abstain (OR = 1·80; 95 % CI 1·29, 2·52), sex (girls v. boys: OR = 2·34; 95 % CI 1·37, 3·98) and socio-economic status (advantaged v. disadvantaged school: OR = 2·08; 95 % CI 1·21, 3·56). Underlying beliefs (i.e. more energy, decreased risk of addiction and friends’ approval) associated with intention as well as perceived barriers (e.g. access to SSB, after an activity that makes you thirsty), and facilitating factors (e.g. access to water) linked to SSB consumption were identified.

Conclusions:

The results can inform public health interventions to decrease SSB consumption and their associated health problems among adolescents.

Social Influences on Obesity: Current Knowledge, Emerging Methods, and Directions for Future Research and Practice

PURPOSE OF REVIEW

Individuals tend to be socially connected with those of similar weight and obesity status. To inform future research and intervention development, we reviewed recent literature examining social influences on weight with a focus on mechanisms of social influence, populations studied, and emerging analytical methods.

RECENT FINDINGS

Social networks appear to influence weight gain and weight loss. It remains unclear what underlying mechanisms (e.g., social norms, social comparison, behavioral modeling) drive this relationship. Stochastic actor-oriented modeling is an important method in the field, but other work has leveraged natural experiment or randomized designs to study social influence. Future networks and obesity research should examine social influence mechanisms, focus on diverse populations across the life course, and carefully consider how to adequately control for competing factors of social selection and physical environments.

Testing a Social Network Intervention Using Vlogs to Promote Physical Activity Among Adolescents: A Randomized Controlled Trial

There is a need to stimulate physical activity among adolescents, but unfortunately, they are hard to reach with traditional mass media interventions. A promising alternative is to carry out social network interventions. In social network interventions, a small group of individuals (influence agents) is selected to promote health-related behaviors within their social network. This study investigates whether a social network intervention is more effective to promote physical activity, compared to a mass media intervention and no intervention. Adolescents (N = 446; M_age = 11.35, SD_age = 1.34; 47% male) were randomly allocated by classroom (N = 26, in 11 schools) to one of three conditions: social network intervention, mass media intervention, or control condition. In the social network intervention, 15% of the participants (based on peer nominations) was approached to become an influence agent, who created vlogs about physical activity that were shown during the intervention. In the mass media intervention, participants were exposed to vlogs made by unfamiliar peers (i.e., vlogs of the social network intervention). The control condition did not receive vlogs about physical activity. All participants received a research smartphone to complete questionnaires and a wrist-worn accelerometer to measure physical activity. The trial was registered a priori in the Dutch Trial Registry (NTR6903). There were no differences in objectively measured physical activity between this social network intervention and the control condition in the short-term, but there was an unexpected increase in the control condition compared to the social network intervention in the long-term. No differences between the social network intervention and mass media intervention were observed. The current study does not provide evidence that this social network intervention is effective in increasing physical activity in adolescents. Exploratory analyses suggest that this social network intervention increased the perceived social norm toward physical activity and responses to the vlogs were more positive in the social network intervention than in the mass media intervention. These initial results warrant further research to investigate the role of the social norms and the added benefit of using influence agents for social network interventions.

Clinical Trial Registration:https://www.trialregister.nl/, identifier NTR6903.

The Impact of Social Media Influencers on Children's Dietary Behaviors

Over the past years vlogs rapidly have become an attractive platform for food industries, sponsoring social media influencers to promote their products. As with more traditional media, social media influencers predominantly promote unhealthy drinks and foods that are high in sugar, fat, and salt - consumption of which may increase the risk of overweight, obesity, and non-communicable diseases. The aim of the current Brief Research Report is to examine the impact of vlogs on children's unhealthy dietary behaviors. Drawing on longitudinal survey data from 453 8- to 12-year-old children, we analyzed the longitudinal relations between children's frequency of watching vlogs and their consumption of unhealthy beverages and snacks. Structural path modeling analyses of three waves of data with 1-year intervals showed that children's self-reported frequency of watching vlogs influenced consumption of unhealthy beverages 2 years later. The analyses did not yield significant relations for Unhealthy Snacks Consumption. The strength of the observed longitudinal relation between children's Frequency of Watching Vlogs and Consumption of unhealthy beverages was comparable to previous findings regarding more traditional types of food marketing.

NASA Mission X Program for Healthy Eating and Active Living among Taiwanese Elementary School Students

PURPOSE

This study assessed the effects of an intervention program adapted from the NASA Mission X (MX) program on children's Healthy Eating Active Living (HEAL) knowledge and behaviors and anthropometry.

METHODS

This clustered randomized control trial recruited 8 elementary schools in remote rural areas of Northern Taiwan. The intervention was the 8-week MX program. All the 3rd and 4th graders were invited to the study (n = 245). Children's weight, height, HEAL knowledge and behaviors were measured pre- and post-intervention.

RESULTS

The intervention group had significantly more improvements than control group in physical activity knowledge score (+0.91 vs. +0.25, p = 0.002), diet knowledge score (+0.62 vs. +0.17, p = 0.044), and score of interests in NASA and space exploration (+0.34 vs. -0.07, p < 0.0001). BMI increased from 18.4 to 18.6 (p < 0.05) for the control group but did not change for the intervention group. The changes in BMI between groups did not differ significantly.

CONCLUSION AND PRACTICE IMPLICATIONS

This randomized controlled trial showed that the NASA MX program was feasible and acceptable among children in Taiwan, and improved children's HEAL knowledge. (ClinicalTrials.gov registration: NCT03355131).

A peer-led physical activity intervention in schools for adolescent girls: a feasibility RCT

Background

Girls are less active than boys and few adolescent girls meet physical activity (PA) guidelines. Peers are an important influence on the views and behaviours of adolescent girls, yet many PA interventions involving peers use formal approaches that may not harness the power of peer groups. More informal peer-led PA interventions, which work within proximal peer groups, may hold promise for increasing girls’ PA.

Objectives

To examine the feasibility, evidence of promise and cost of the Peer-Led physical Activity iNtervention for Adolescent girls (PLAN-A), a peer-led PA intervention.

Design

Phase 1 comprised formative work and a pilot study conducted in one secondary school. Phase 2 was a feasibility study comprising a pilot randomised controlled trial in six secondary schools, including process and economic evaluations.

Setting

Six secondary schools in South Gloucestershire and Wiltshire, recruited from schools above the median local Pupil Premium (i.e. more deprived).

Participants

Year 8 girls (aged 12–13 years).

Intervention

Year 8 girls nominated other girls in their year who are likely to be influential (e.g. who they look up to, are good listeners); the 18% most nominated were invited to be peer supporters (PSs). PSs attended 2 consecutive days of training (plus a top-up day 5 weeks later) outside the school site, led by pairs of PS trainers, to increase their knowledge about PA and their capabilities and confidence to promote PA in their friendship group.

Main outcome measures

Measures focused on establishing evidence for feasibility and promise: recruitment and retention of Year 8 girls and PSs, data provision rates [accelerometer and questionnaire collected pre randomisation/beginning of Year 8 (T0), end of Year 8 (T1) and beginning of Year 9 (T2)], intervention acceptability, PS training attendance, intervention cost, and the between-arm difference in weekday minutes of moderate to vigorous PA (MVPA). A process evaluation was conducted.

Results

Six schools were recruited: four PLAN-A (n = 269) and two control (n = 158). In total, 94.7% of Year 8 girls participated. A total of 55 (17–24% of Year 8 girls) PSs were trained (attendance rate 91–100%). Five girls were trained as PS trainers. Questionnaire data provision exceeded 92% at all time points. Accelerometer return rates were > 85% and wear-time criteria were met by 83%, 71% and 62% of participants at T0, T1 and T2, respectively. Mean weekday MVPA did not differ between intervention arms at T1 (1.1 minutes, 95% CI –4.3 to 6.5 minutes) but did at T2 (6.1 minutes, 95% CI 1.4 to 10.8 minutes), favouring PLAN-A. The mean cost of intervention delivery was £2685 per school or £37 per Year 8 girl. Process evaluation identified good fidelity, engagement and enjoyment of the PS training and peer-support strategies. PSs needed more guidance on how to start conversations.

Limitations

Accelerometer data provision was lowest at T2, suggesting a need for strategies to increase compliance.

Conclusions

Informal peer-led intervention approaches, such as PLAN-A, hold promise as a means of promoting PA to adolescent girls.

Future work

A definitive randomised controlled trial of PLAN-A is warranted.

Trial registration

Current Controlled Trials ISRCTN12543546.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 7, No. 16. See the NIHR Journals Library website for further project information. The work was undertaken with the support of the Centre for the Development and Evaluation of Complex Interventions for Public Health Improvement (DECIPHer), a UK Clinical Research Collaboration (UKCRC) Public Health Research Centre of Excellence. Joint funding (MR/KO232331/1) from the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, the Welsh Government and the Wellcome Trust, under the auspices of the UKCRC, is gratefully acknowledged. This study was designed and delivered in collaboration with the Bristol Randomised Trials Collaboration (BRTC), a UK CRC-registered clinical trials unit in receipt of NIHR clinical trials unit support funding. The intervention costs were jointly funded by South Gloucestershire Council and Wiltshire Council.

Teachers as Healthy Beverage Role Models: Relationship of Student and Teacher Beverage Choices in Elementary Schools

Schools are a key setting for curbing student intake of sugar-sweetened beverages (SSBs). While studies suggest that restrictions on SSBs, increased access to healthier beverages, and education about the importance of drinking water instead of SSBs can promote healthier beverage patterns among students, there is little known about the impact that teachers' own beverage choices can have on those of their students. Data were drawn from cross-sectional surveys administered as part of a larger evaluation of a drinking water access and promotion intervention in public elementary schools in the San Francisco Bay Area region of California. Descriptive statistics were used to examine teacher (n = 56) and student (n = 1176) self-reported beverage consumption at school. Mixed-effects logistic regression was used to examine associations between teacher and student beverage intake adjusting for clustering of students by teacher. Teachers were also surveyed via open-ended questions about strategies to increase student water consumption at school. Nearly all teachers reported drinking water during the school day (95%), often in front of students. Teacher SSB intake was rare (9%). Students whose teachers drank water in front of their classes were significantly more likely to report drinking water during the school day. Teachers tend to select healthy beverages at work and may serve as role models to encourage student consumption of water instead of SSBs.

Identifying Influence Agents That Promote Physical Activity Through the Simulation of Social Network Interventions: Agent-Based Modeling Study

Background

Social network interventions targeted at children and adolescents can have a substantial effect on their health behaviors, including physical activity. However, designing successful social network interventions is a considerable research challenge. In this study, we rely on social network analysis and agent-based simulations to better understand and capitalize on the complex interplay of social networks and health behaviors. More specifically, we investigate criteria for selecting influence agents that can be expected to produce the most successful social network health interventions.

Objective

The aim of this study was to test which selection criterion to determine influence agents in a social network intervention resulted in the biggest increase in physical activity in the social network. To test the differences among the selection criteria, a computational model was used to simulate different social network interventions and observe the intervention’s effect on the physical activity of primary and secondary school children within their school classes. As a next step, this study relied on the outcomes of the simulated interventions to investigate whether social network interventions are more effective in some classes than others based on network characteristics.

Methods

We used a previously validated agent-based model to understand how physical activity spreads in social networks and who was influencing the spread of behavior. From the observed data of 460 participants collected in 26 school classes, we simulated multiple social network interventions with different selection criteria for the influence agents (ie, in-degree centrality, betweenness centrality, closeness centrality, and random influence agents) and a control condition (ie, no intervention). Subsequently, we investigated whether the detected variation of an intervention’s success within school classes could be explained by structural characteristics of the social networks (ie, network density and network centralization).

Results

The 1-year simulations showed that social network interventions were more effective compared with the control condition (beta=.30; t100=3.23; P=.001). In addition, the social network interventions that used a measure of centrality to select influence agents outperformed the random influence agent intervention (beta=.46; t100=3.86; P<.001). Also, the closeness centrality condition outperformed the betweenness centrality condition (beta=.59; t100=2.02; P=.046). The anticipated interaction effects of the network characteristics were not observed.

Conclusions

Social network intervention can be considered as a viable and promising intervention method to promote physical activity. We demonstrated the usefulness of applying social network analysis and agent-based modeling as part of the social network interventions’ design process. We emphasize the importance of selecting the most successful influence agents and provide a better understanding of the role of network characteristics on the effectiveness of social network interventions.

Environmental interventions to reduce the consumption of sugar-sweetened beverages and their effects on health

BACKGROUND

Frequent consumption of excess amounts of sugar-sweetened beverages (SSB) is a risk factor for obesity, type 2 diabetes, cardiovascular disease and dental caries. Environmental interventions, i.e. interventions that alter the physical or social environment in which individuals make beverage choices, have been advocated as a means to reduce the consumption of SSB.

OBJECTIVES

To assess the effects of environmental interventions (excluding taxation) on the consumption of sugar-sweetened beverages and sugar-sweetened milk, diet-related anthropometric measures and health outcomes, and on any reported unintended consequences or adverse outcomes.

SEARCH METHODS

We searched 11 general, specialist and regional databases from inception to 24 January 2018. We also searched trial registers, reference lists and citations, scanned websites of relevant organisations, and contacted study authors.

SELECTION CRITERIA

We included studies on interventions implemented at an environmental level, reporting effects on direct or indirect measures of SSB intake, diet-related anthropometric measures and health outcomes, or any reported adverse outcome. We included randomised controlled trials (RCTs), non-randomised controlled trials (NRCTs), controlled before-after (CBA) and interrupted-time-series (ITS) studies, implemented in real-world settings with a combined length of intervention and follow-up of at least 12 weeks and at least 20 individuals in each of the intervention and control groups. We excluded studies in which participants were administered SSB as part of clinical trials, and multicomponent interventions which did not report SSB-specific outcome data. We excluded studies on the taxation of SSB, as these are the subject of a separate Cochrane Review.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened studies for inclusion, extracted data and assessed the risks of bias of included studies. We classified interventions according to the NOURISHING framework, and synthesised results narratively and conducted meta-analyses for two outcomes relating to two intervention types. We assessed our confidence in the certainty of effect estimates with the GRADE framework as very low, low, moderate or high, and presented 'Summary of findings' tables.

MAIN RESULTS

We identified 14,488 unique records, and assessed 1030 in full text for eligibility. We found 58 studies meeting our inclusion criteria, including 22 RCTs, 3 NRCTs, 14 CBA studies, and 19 ITS studies, with a total of 1,180,096 participants. The median length of follow-up was 10 months. The studies included children, teenagers and adults, and were implemented in a variety of settings, including schools, retailing and food service establishments. We judged most studies to be at high or unclear risk of bias in at least one domain, and most studies used non-randomised designs. The studies examine a broad range of interventions, and we present results for these separately.Labelling interventions (8 studies): We found moderate-certainty evidence that traffic-light labelling is associated with decreasing sales of SSBs, and low-certainty evidence that nutritional rating score labelling is associated with decreasing sales of SSBs. For menu-board calorie labelling reported effects on SSB sales varied.Nutrition standards in public institutions (16 studies): We found low-certainty evidence that reduced availability of SSBs in schools is associated with decreased SSB consumption. We found very low-certainty evidence that improved availability of drinking water in schools and school fruit programmes are associated with decreased SSB consumption. Reported associations between improved availability of drinking water in schools and student body weight varied.Economic tools (7 studies): We found moderate-certainty evidence that price increases on SSBs are associated with decreasing SSB sales. For price discounts on low-calorie beverages reported effects on SSB sales varied.Whole food supply interventions (3 studies): Reported associations between voluntary industry initiatives to improve the whole food supply and SSB sales varied.Retail and food service interventions (7 studies): We found low-certainty evidence that healthier default beverages in children's menus in chain restaurants are associated with decreasing SSB sales, and moderate-certainty evidence that in-store promotion of healthier beverages in supermarkets is associated with decreasing SSB sales. We found very low-certainty evidence that urban planning restrictions on new fast-food restaurants and restrictions on the number of stores selling SSBs in remote communities are associated with decreasing SSB sales. Reported associations between promotion of healthier beverages in vending machines and SSB intake or sales varied.Intersectoral approaches (8 studies): We found moderate-certainty evidence that government food benefit programmes with restrictions on purchasing SSBs are associated with decreased SSB intake. For unrestricted food benefit programmes reported effects varied. We found moderate-certainty evidence that multicomponent community campaigns focused on SSBs are associated with decreasing SSB sales. Reported associations between trade and investment liberalisation and SSB sales varied.Home-based interventions (7 studies): We found moderate-certainty evidence that improved availability of low-calorie beverages in the home environment is associated with decreased SSB intake, and high-certainty evidence that it is associated with decreased body weight among adolescents with overweight or obesity and a high baseline consumption of SSBs.Adverse outcomes reported by studies, which may occur in some circumstances, included negative effects on revenue, compensatory SSB consumption outside school when the availability of SSBs in schools is reduced, reduced milk intake, stakeholder discontent, and increased total energy content of grocery purchases with price discounts on low-calorie beverages, among others. The certainty of evidence on adverse outcomes was low to very low for most outcomes.We analysed interventions targeting sugar-sweetened milk separately, and found low- to moderate-certainty evidence that emoticon labelling and small prizes for the selection of healthier beverages in elementary school cafeterias are associated with decreased consumption of sugar-sweetened milk. We found low-certainty evidence that improved placement of plain milk in school cafeterias is not associated with decreasing sugar-sweetened milk consumption.

AUTHORS' CONCLUSIONS

The evidence included in this review indicates that effective, scalable interventions addressing SSB consumption at a population level exist. Implementation should be accompanied by high-quality evaluations using appropriate study designs, with a particular focus on the long-term effects of approaches suitable for large-scale implementation.

Eating for Two? Protocol of an Exploratory Survey and Experimental Study on Social Norms and Norm-Based Messages Influencing European Pregnant and Non-pregnant Women's Eating Behavior

The social context is an important factor underlying unhealthy eating behavior and the development of inappropriate weight gain. Evidence is accumulating that powerful social influences can also be used as a tool to impact people's eating behavior in a positive manner. Social norm-based messages have potential to steer people in making healthier food choices. The research field on nutritional social norms is still emerging and more research is needed to gain insights into why some people adhere to social norms whereas others do not. There are indications stemming from empirical studies on social eating behavior that this may be due to ingratiation purposes and uncertainty reduction. That is, people match their eating behavior to that of the norm set by their eating companion(s) in order to blend in and be part of the group. In this project, we explore nutritional social norms among pregnant women. This population is particularly interesting because they are often subject to unsolicited advice and experience social pressure from their environment. In addition, their pregnancy affects their body composition, eating pattern, and psychosocial status. Pregnancy provides an important window of opportunity to impact health of pregnant women and their child. Nevertheless, the field of nutritional social norms among pregnant women is understudied and more knowledge is needed on whether pregnant women use guidelines from their social environment for their own eating behavior. In this project we aim to fill this research gap by means of an exploratory survey (Study 1) assessing information about social expectations, (mis)perceived social norms and the role of different reference groups such as other pregnant women, family, and friends. In addition, we conduct an online experiment (Study 2) testing to what extent pregnant women are susceptible to social norm-based messages compared to non-pregnant women. Moreover, possible moderators are explored which might impact women's susceptibility to social norms as well as cultural aspects that co-determine which social norms and guidelines exist. The project's findings could help design effective intervention messages in promoting healthy eating behavior specifically targeted to European pregnant women.

A randomized controlled trial testing a social network intervention to promote physical activity among adolescents

BACKGROUND

The current study examined the effectiveness of a social network intervention to promote physical activity among adolescents. Social network interventions utilize peer influence to change behavior by identifying the most influential individuals within social networks (i.e., influence agents), and training them to promote the target behavior.

METHOD

A total of 190 adolescents (46.32% boys; M age = 12.17, age range: 11-14 years) were randomly allocated to either the intervention or control condition. In the intervention condition, the most influential adolescents (based on peer nominations of classmates) in each classroom were trained to promote physical activity among their classmates. Participants received a research smartphone to complete questionnaires and an accelerometer to measure physical activity (steps per day) at baseline, and during the intervention one month later.

RESULTS

A multilevel model tested the effectiveness of the intervention, controlling for clustering of data within participants and days. No intervention effect was observed, b = .04, SE = .10, p = .66.

CONCLUSION

This was one of the first studies to test whether physical activity in adolescents could be promoted via influence agents, and the first social network intervention to use smartphones to do so. Important lessons and implications are discussed concerning the selection criterion of the influence agents, the use of smartphones in social network intervention, and the rigorous analyses used to control for confounding factors.

TRIAL REGISTRATION

Dutch Trial Registry (NTR): NTR6173 . Registered 5 October 2016 Study procedures were approved by the Ethics Committee of the Radboud University (ECSW2014-100614-222).

Youth's social network structures and peer influences: study protocol MyMovez project - Phase I

Background

Youth are an important target group for social network interventions, because they are particularly susceptible to the adaptation of healthy and unhealthy habits and behaviors of others. They are surrounded by ‘social influence agents’ (i.e., role models such as family, friends and peers) that co-determine their dietary intake and physical activity. However, there is a lack of systematic and comprehensive research on the implementation of a social network approach in health campaigns. The MyMovez research project aims to fill this gap by developing a method for effective social network campaign implementation. This protocol paper describes the design and methods of Phase I of the MyMovez project, aiming to unravel youth’s social network structures in combination with individual, psychosocial, and environmental factors related to energy intake and expenditure. In addition, the Wearable Lab is developed to enable an attractive and state-of-the-art way of collecting data and online campaign implementation via social networks.

Methods

Phase I of the MyMovez project consists of a large-scale cross-sequential cohort study (N = 953; 8-12 and 12-15 y/o). In five waves during a 3-year period (2016-2018), data are collected about youth’s social network exposure, media consumption, socialization experiences, psychological determinants of behavior, physical environment, dietary intake (snacking and drinking behavior) and physical activity using the Wearable Lab. The Wearable Lab exists of a smartphone-based research application (app) connected to an activity tracking bracelet, that is developed throughout the duration of the project. It generates peer- and self-reported (e.g., sociometric data and surveys) and experience sampling data, social network beacon data, real-time physical activity data (i.e., steps and cycling), location information, photos and chat conversation data from the app’s social media platform Social Buzz.

Discussion

The MyMovez project - Phase I is an innovative cross-sequential research project that investigates how social influences co-determine youth’s energy intake and expenditure. This project utilizes advanced research technologies (Wearable Lab) that provide unique opportunities to better understand the underlying processes that impact youths’ health-related behaviors. The project is theoretically and methodologically pioneering and produces a unique and useful method for successfully implementing and improving health campaigns.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5353-5) contains supplementary material, which is available to authorized users.

Promoting Water Consumption on a Caribbean Island: An Intervention Using Children's Social Networks at Schools

Sugar-sweetened beverage (SSB) consumption and the associated childhood obesity are major concerns in the Caribbean, creating a need for interventions promoting water consumption as a healthy alternative. A social network-based intervention (SNI) was tested among Aruban children to increase their water consumption and behavioral intention to do so and, consequently, to decrease SSB consumption and the associated behavioral intention. In this study, the moderating effects of descriptive and injunctive norms were tested. A cluster randomized controlled trial was completed in schools (mean age = 11 years ± SD = 0.98; 54% girls). Children were assigned to the intervention group (IG; n = 192) or control group (CG; n = 185). IG children were exposed to peer influencers promoting water consumption and CG children were not. Regression analyses showed that water consumption increased for IG children with a high injunctive norm score (p = 0.05); however, their intention to consume more water remained unchanged (p = 0.42). Moreover, IG children showed a decrease in SSB consumption (p = 0.04) and an increase in their intention to consume less SSB (p = 0.00). These findings indicate that SNIs are a promising instrument for health behavioral changes for Aruba and other islands in the Caribbean region.