The role of psychosocial well-being and emotion-driven impulsiveness in food choices of European adolescents.

BACKGROUND: It is unclear whether a hypothetical intervention targeting either psychosocial well-being or emotion-driven impulsiveness is more effective in reducing unhealthy food choices. Therefore, we aimed to compare the (separate) causal effects of psychosocial well-being and emotion-driven impulsiveness on European adolescents' sweet and fat propensity. METHODS: We included 2,065 participants of the IDEFICS/I.Family cohort (mean age: 13.4) providing self-reported data on sweet propensity (score range: 0 to 68.4), fat propensity (range: 0 to 72.6), emotion-driven impulsiveness using the UPPS-P negative urgency subscale, and psychosocial well-being using the KINDLR Questionnaire. We estimated, separately, the average causal effects of psychosocial well-being and emotion-driven impulsiveness on sweet and fat propensity applying a semi-parametric doubly robust method (targeted maximum likelihood estimation). Further, we investigated a potential indirect effect of psychosocial well-being on sweet and fat propensity mediated via emotion-driven impulsiveness using a causal mediation analysis. RESULTS: If all adolescents, hypothetically, had high levels of psychosocial well-being, compared to low levels, we estimated a decrease in average sweet propensity by 1.43 [95%-confidence interval: 0.25 to 2.61]. A smaller effect was estimated for fat propensity. Similarly, if all adolescents had high levels of emotion-driven impulsiveness, compared to low levels, average sweet propensity would be decreased by 2.07 [0.87 to 3.26] and average fat propensity by 1.85 [0.81 to 2.88]. The indirect effect of psychosocial well-being via emotion-driven impulsiveness was 0.61 [0.24 to 1.09] for average sweet propensity and 0.55 [0.13 to 0.86] for average fat propensity. CONCLUSIONS: An intervention targeting emotion-driven impulsiveness, compared to psychosocial well-being, would be marginally more effective in reducing sweet and fat propensity in adolescents.

The association between commuting and cardiovascular disease: A biomarker-based analysis of cross-sectional cohort data from the UK Biobank.

This study used cross-sectional UK Biobank data to estimate the influence of active and passive commuting modes and commuting distance on cardiovascular disease (CVD) -related biomarkers as measures of health outcomes. The analysis applied logistic regression to assess the risk of exhibiting individual biomarker values outside a predefined reference interval and standard linear regression to estimate the relation between commuting practices and a composite CVD index. The study sample comprised 208,893 UK Biobank baseline survey participants aged 40 to 69 who use various modes of transport to commute to work at least once a week. Participants were recruited and interviewed between 2006 and 2010 at 22 centers geographically dispersed across England, Scotland, and Wales. The data set included these participants' sociodemographic and health-related information, including lifestyle indicators and biological measures. The primary outcome was a shift from low to high-risk blood serum levels in eight cardiovascular biomarkers: total cholesterol, low density lipoprotein, high density lipoprotein, triglycerides, apolipoprotein A and B, C-reactive protein, and lipoprotein (a). Our results indicated a small negative association between the composite risk index for CVD biomarkers and weekly commuting distance. Although estimates for active commuting modes (cycling, walking) may admittedly be sensitive to different covariate adjustments, our specifications show them to be positively associated with select CVD biomarkers. Commuting long distances by car is negatively associated with CVD-related biomarkers, while cycling and walking might be positively associated. This biomarker-based evidence, although limited, is less susceptible to residual confounding than that from distant outcomes like CVD mortality.

What we know about the actual implementation process of public physical activity policies: results from a scoping review.

BACKGROUND: Physical inactivity rates have remained high worldwide since 2001. Public policies are an essential upstream lever to target individual physical activity (PA) behaviour. However, implementers have different strategies and face implementation challenges that are poorly understood. The present study analyzes the implementation processes of public policies to promote PA in terms of: (i) the policies covered and their legal quality, (ii) the actors and stakeholders involved in the implementation process and (iii) the used implementation strategies (vertical, horizontal or a mix). METHODS: A scoping review was systematically conducted (registered Open Science Framework: osf.io/7w84q/), searching 10 databases and grey literature until March 2022. Of the 7741 titles and abstracts identified initially, 10 studies were included. RESULTS: The current evidence includes high-income countries (USA, n = 7; UK, New Zealand and Oman, n = 1 each). Policy areas covered are education (school sector) and PA promotion in general (national PA plans or city-wide approaches). The legal classification ranges from laws (school sector) to coordination and budgeting to non-legally binding recommendations. The jurisdictions covered were federal (n = 4), state (n = 1), county (n = 1), school district (n = 1) and city (n = 3). Implementation strategies for city-wide approaches are characterized by a coordinated approach with vertical and horizontal integration; federal PA policies by a mix of implementation strategies; and the school sector by a strict horizontal top-down integration without the involvement of other actors. CONCLUSION: Implementation strategies differ by policy field. Therefore, continuous evaluation of the implementation process is necessary to align policy implementation with policy goals to promote individual PA behaviour.

Sustainable Urban Mobility Plans: implementation process and indicators to evaluate effects on physical activity.

BACKGROUND: Active mobility and public transport increase physical activity (PA) levels. With varying intensity and effectiveness, European cities implement Sustainable Urban Mobility Plans (SUMPs) to spur transport-related PA. Therefore, we aim to examine drivers and barriers to SUMP implementation and assess its influence on PA across European cities. METHODS: We screened policy reports to gain insights into SUMP implementation in one Danish, two German and two Polish cities. Further, we conducted semi-structured interviews with SUMP stakeholders in these cities to explore their experiences with SUMP implementation. Thematic analysis of interview transcripts was applied to identify similarities and differences across cities. To assess the effect of SUMP implementation on PA, we searched for data on indicators of transport-related PA. RESULTS: All investigated cities are committed to sustainable mobility. Nonetheless, complex institutional structures, the dominant role of motorized traffic as well as complex regional and local policy integration hamper SUMP implementation. Danish, German and Polish cities face different contexts in terms of financing, national guidelines and the prominence of sustainability as a policy objective. Each city adopts unique indicators for monitoring the effects of SUMPs on transport-related PA. The variety of indicators and limited data availability impede a comparative evaluation across cities. Constrained by this restriction, we identified motorization rate, modal split and public transport ridership as suitable indicators. CONCLUSIONS: Local idiosyncrasies need to be accounted for when assessing the implementation of SUMPs. Nonetheless, consistent indicators and data transparency are essential for comparing the effectiveness of SUMPs and their impact on PA.

Battle of the primes - The effect and interplay of health and hedonic primes on food choice.

People making food choices are often exposed to different cues that can activate relevant goals that influence the choice outcome. Hedonic goals are frequently primed by advertising while health policy enlists primes that activate health goals in the moment of food decision-making - e.g., healthy food labels. However, little is known about the effect of such goal-priming cues on the population level and how people respond when exposed to both types of primes simultaneously. The results of this study, based on a large, representative sample (N = 1200), show no effect of health-goal priming on healthy food choices. Being exposed to a sole hedonic prime, however, reduces healthy choices by 3%. This effect completely disappeared when both primes were presented at the same time. All effects remained insensitive to people's gender, hunger status, level of dietary restraint, and BMI. These findings cast doubt over the effectiveness of health goal primes as a tool to increase healthy food choices but suggest a protective effect against competing hedonic primes and could thereby prevent less healthy choices.

"Corona Cooking": The interrelation between emotional response to the first lockdown during the COVID-19 pandemic and cooking attitudes and behaviour in Denmark.

For this study, the authors measured attitudes toward shopping for food and cooking, before and during the first lockdown due to the COVID-19 pandemic, among a sample of 526 Danish consumers, using an online survey. To analyse changes due to the lockdown, they applied a latent class Markov model, which revealed four states: middle of the road, love cooking (and like shopping), like shopping and cooking, and do not like shopping or cooking. In estimating transition probabilities, the findings reveal that most respondents remained in the same state before and during the lockdown, but those that changed were more likely to exhibit relatively higher liking of shopping and cooking. These states also reflect variations in people's food literacy and self-reported food consumption. Finally, respondents with stronger negative emotional reactions to the lockdown were more likely to change their states.

Associations Between Psychosocial Well-Being, Stressful Life Events and Emotion-Driven Impulsiveness in European Adolescents.

Knowing the extent to which mental well-being and stressful life events during adolescence contribute to personality characteristics related to risk-taking behaviors, such as emotion-driven impulsiveness, is highly relevant for the development of health promotion measures. This study examined whether psychosocial well-being and different stressful life events are associated with emotion-driven impulsiveness. In total, 3,031 adolescents (52% girls; Mage = 13.6 years) were included from the I. Family Study, a cross-sectional examination on lifestyle-related behaviors conducted across eight European countries in 2013/14. Linear mixed-effects regression models showed that higher psychosocial well-being was associated with lower emotion-driven impulsiveness independent of socio-demographic, health-related, and parental variables. A higher number of stressful life events was associated with higher emotion-driven impulsiveness. Psychosocial well-being and stressful life events need to be further considered in the development and tailoring of health promotion strategies that aim to reduce emotion-driven impulsiveness.

Ultra-processed foods consumption and diet quality of European children, adolescents and adults: Results from the I.Family study.

BACKGROUND AND AIMS: Food processing has been indicated as a factor capable of negatively affecting the global food system, including the profile of consumers' diets. The objectives of the present study were to provide a description of the consumption of ultra-processed foods (UPFs) in the large population of children, adolescents and adults from eight European countries participating to the I.Family study, and to investigate the association between UPFs intake and nutritional quality of the diet. METHODS AND RESULTS: Dietary intake was assessed using a 24-h dietary recall. The quality of the diet was evaluated by the Healthy Dietary Adherence Score (HDAS) using an FFQ. UPFs were classified according to the NOVA classification. Almost half of the daily energy intake of the 7073 participants came from UPFs, and this trend decreased progressively with age. UPFs contributed more than 50 % of the daily intake of total and saturated fat, carbohydrates and about 70 % of sugars intake in children and adolescents. No differences in UPFs consumption were found according to the educational and socio-economic status of the population. Energy intake increased across the quintiles of UPFs intake, while HDAS decreased. The frequency of consumption of fruit and vegetable, fish, and fibre rich foods was low in the fifth quintile of UPFs intake, both in adolescents and in adults. The consumption of foods rich in calories and low in nutritional content, operationally defined as "junk food", was significantly higher in the fifth quintile. CONCLUSIONS: In the population of the European I.Family study, UPFs contributed a large proportion of the daily energy intake, especially in children and adolescents. Higher consumption of UPFs was associated with a lower quality of the diet. REGISTRATION NUMBER FOR CLINICAL TRIALS: ISRCTN62310987.

Nudging healthier food choices in a cafeteria setting: A sequential multi-intervention field study.

Creating more health-fostering environments is high on the agenda of public and private actors. The behavioral approach to nudge people towards healthier food choices is gaining popularity despite limited understanding about where, and for whom, which specific nudges work. This study contributes by reporting on three different nudging interventions in the same setting and presents effects on different sub-populations. We find overall small effects that are heterogeneous, ranging from robustly more to even less healthy choices. We discuss the importance of transparency and reactance to health interventions and the potential interplay of interventions with habitual behavior among different sub-populations.

A cross-sectional study of obesogenic behaviours and family rules according to family structure in European children.

BACKGROUND: There has been an increase in children growing up in non-traditional families, such as single-parent and blended families. Children from such families have a higher prevalence of obesity and poorer health outcomes, but research on the relationship with obesogenic behaviours is limited. OBJECTIVES: Therefore, the aim of this study was to investigate whether there are associations between family structures and obesogenic behaviours and related family rules in European children and adolescents. METHODS: The sample included 7664 children (mean age ± SD: 10.9 ± 2.9) from 4923 families who were participants of the multi-centre I.Family study (2013/2014) conducted in 8 European countries. Family structure was assessed by a detailed interview on kinship and household. Obesogenic behaviours (screen time, sleep duration, consumption of sugar-sweetened beverages (SSBs)) and family rules (rules for computer and television, bedtime routine, availability of SSBs during meals) were determined by standardized questionnaires. Multilevel mixed-effects linear and logistic regression models were used to model the associations of family structure with obesogenic behaviours and family rules. Sex, age, parental education level, number of children and adults in the household and BMI z-score were covariates in the models. Two-parent biological families were set as the reference category. RESULTS: Children from single-parent families were less likely to have family rules regarding screen time (OR: 0.62, 95% CI: 0.40-0.94, p = 0.026) with higher reported hours of screen time per week (ß = 2.70 h/week, 95% CI: 1.39-4.00, p < 0.001). The frequency of weekly SSB consumption differed by family structure in a sex-specific manner: girls from single-parent (ß = 3.19 frequency/week, 95% CI: 0.91-5.47, p = 0.006) and boys from blended/adoptive families (ß = 3.01 frequency/week, 95% CI: 0.99-5.03, p = 0.004) consumed more SSBs. Sleep duration, bedtime routines and availability of SSBs during meals did not differ between children from these family structures. Parental education did not modify any of these associations. CONCLUSIONS: Parents in non-traditional family structures appear to experience more difficulties in restricting screen time and the intake of SSBs in their children than parents in traditional two-parent family structures. Our findings therefore suggest that additional support and effective strategies for parents in non-traditional families may help to reduce obesogenic behaviours in children from such family types.

Association between variants of neuromedin U gene and taste thresholds and food preferences in European children: Results from the IDEFICS study.

AIM: The neuropeptide neuromedin U (NMU) known for its role in appetite, feeding and energy balance could be involved in the control of food choice and taste sensitivity. We examined the association between NMU polymorphisms/haplotypes and taste thresholds and food preferences in a population of European children. METHODS: A total of 578 subjects from the IDEFICS study (mean age 7.5 ±â€¯0.8 SD, boys 53.6%) with NMU genotype data and food preference (salty, fatty, sweet, flavour and umami food) and taste threshold (salt, fat, sweet, umami) tests available were analysed. Three single nucleotide polymorphisms (SNPs; rs6827359, T:C; rs12500837, T:C; rs9999653, C:T) of NMU gene were analyzed and five major haplotypes were inferred. The associations between genotypes and food preferences or taste thresholds were investigated (odds ratios -OR, adjusted for age, sex and country). A p < 0.05 after false discovery rate adjustment (pFDR) was considered statistically significant. RESULTS: The association between NMU genotypes and food preference showed two NMU SNPs associated with preference for food containing sodium glutamate (umami taste; rs6827359C, OR = 1.61, 95% confidence interval (CI):1.20-2.17; rs9999653T, OR = 1.59, 95%CI:1.18-2.13). In the haplotype analysis, the CTT haplotype showed an OR of 1.70 (95%CI:1.16-2.5) for the umami food preference, while CCT haplotype showed an OR of 1.63 (95%CI:1.11-2.40), compared to the most frequent haplotype (TTC). Carriers of CCT/CCT vs subjects with no CCT haplotype showed an OR of 4.78 (95%CI:1.86-12.30). Umami food preference was associated with low values of BMI z-score, arm circumferences, skinfolds and fat mass (pFDR<0.05). No association between NMU genetic variants and taste thresholds was found. CONCLUSIONS: This study shows for the first time in children an association between preference for umami food and a NMU haplotype, previously found associated with low BMI values.

Emotion-driven impulsiveness but not decision-making ability and cognitive inflexibility predicts weight status in adults.

In this study we aimed to determine whether decision-making ability, cognitive inflexibility and emotion-driven impulsiveness are associated with weight status as expressed by body mass index (BMI), percentage body fat, waist circumference and skinfold thickness in adults from eight different European countries taking part in the I.Family study. The Bechara Gambling Task was used to assess decision-making ability (n = 1717). The Berg Card Sorting Test was used to measure cognitive inflexibility (n = 1509). Lastly, the negative urgency subscale from the UPPS-P Impulsive Behavior Scale was used to measure emotion-driven impulsiveness (n = 4450). Hierarchical regression analyses showed that more emotion-driven impulsiveness was statistically significantly associated with a higher BMI, a higher percentage body fat, and a larger waist circumference in adults, controlling for age, sex, socioeconomic status, country and binge eating; but not with skinfold thickness. Cognitive inflexibility and decision-making ability were not statistically significantly associated with any of the weight status related variables. These results support that impulsivity in response to negative emotions, but not decision-making ability or cognitive inflexibility, is associated with the susceptibility to excessive weight (as indicated by a higher BMI, a higher percentage body fat, and a larger waist circumference). In people behaving impulsively when emotional, focusing on reducing negative affect or improving coping skills is of interest in interventions targeting obesity. CLINICAL TRIAL REGISTRATION: The I.Family study is registered in the ISRCTN registry (ISRCTN62310987) on February 23, 2018.

Palatable food consumption in children: interplay between (food) reward motivation and the home food environment.

To understand the importance of the home food environment on unhealthy food consumption in children high in reward sensitivity, this study tested the hypothesis that the home availability of unhealthy food moderates the effect of reward sensitivity on children's fast-food consumption frequency, exerted via food cue responsiveness. Children between 7.5 and 14 years (n = 174, 50.6% boys) reported on reward sensitivity and food cue responsiveness (by means of the subscale 'external eating'). Their height and weight were measured. Parents reported on their children's fast-food consumption frequency, food cue responsiveness (by means of the subscale 'food responsiveness'), and on the home availability of unhealthy foods. Two moderated mediation models were conducted, one with the parent- and one with the child-reported food cue responsiveness as mediator. Findings suggested that with a high home availability of unhealthy foods, (a) a higher fast-food consumption frequency was found in children high in reward sensitivity and (b) the relation between reward sensitivity and the fast-food consumption frequency was mediated by external eating. CONCLUSIONS: The findings point at the importance of the home food environment in children high in reward sensitivity. They suggest to limit the home availability of unhealthy foods. What is Known: • Reward sensitivity (RS) is positively associated with children's palatable food consumption • In adolescents, this effect is mediated by food cue responsiveness, which determines the strength of an individual's motivation to obtain food when perceiving food cues What is New: • Children high in RS may be more vulnerable to palatable food cues in their everyday food environment because of a higher food cue responsiveness • The home food environment may be an important determining factor of the palatable food consumption of these children.

Pester power and its consequences: do European children's food purchasing requests relate to diet and weight outcomes?

OBJECTIVE: Children may influence household spending through 'pester power'. The present study examined pestering through parent-child food shopping behaviours in relation to children's diet and weight status. DESIGN: Cross-sectional and prospective analyses drawn from the IDEFICS study, a cohort study of parents and their children. Children's height and weight were measured and their recent diets were reported by parental proxy based on the Children's Eating Habits Questionnaire-FFQ at baseline and 2-year follow-up. Parents also completed questionnaires at both time points about pestering, including whether the child goes grocery shopping with them, asks for items seen on television and is bought requested food items. SETTING: Participants were recruited from eight European countries for the IDEFICS study (non-nationally representative sample). SUBJECTS: Study participants were children aged 2-9 years at enrolment and their parents. A total of 13 217 parent-child dyads were included at baseline. Two years later, 7820 of the children were re-examined. RESULTS: Most parents (63 %) at baseline reported 'sometimes' acquiescing to their children's requests to purchase specific foods. Pestering was modestly associated with weight and diet. At baseline, children whose parents 'often' complied consumed more high-sugar and high-fat foods. Children who 'often' asked for items seen on television were likely to become overweight after 2 years (OR=1·31), whereas 'never' asking protected against overweight (OR=0·72). CONCLUSIONS: Pestering was modestly related to diet and weight in cross-sectional, but not longitudinal analyses. Asking for items seen on television had the most robust relationships across child outcomes and over time.

A longitudinal causal graph analysis investigating modifiable risk factors and obesity in a European cohort of children and adolescents.

Childhood obesity is a complex disorder that appears to be influenced by an interacting system of many factors. Taking this complexity into account, we aim to investigate the causal structure underlying childhood obesity. Our focus is on identifying potential early, direct or indirect, causes of obesity which may be promising targets for prevention strategies. Using a causal discovery algorithm, we estimate a cohort causal graph (CCG) over the life course from childhood to adolescence. We adapt a popular method, the so-called PC-algorithm, to deal with missing values by multiple imputation, with mixed discrete and continuous variables, and that takes background knowledge such as the time-structure of cohort data into account. The algorithm is then applied to learn the causal structure among 51 variables including obesity, early life factors, diet, lifestyle, insulin resistance, puberty stage and cultural background of 5112 children from the European IDEFICS/I.Family cohort across three waves (2007-2014). The robustness of the learned causal structure is addressed in a series of alternative and sensitivity analyses; in particular, we use bootstrap resamples to assess the stability of aspects of the learned CCG. Our results suggest some but only indirect possible causal paths from early modifiable risk factors, such as audio-visual media consumption and physical activity, to obesity (measured by age- and sex-adjusted BMI z-scores) 6 years later.

Healthy eating in the wild: An experience-sampling study of how food environments and situational factors shape out-of-home dietary success.

Across many parts of the world, people increasingly eat out-of-home. Simultaneously, many people strive to eat a healthier diet, but it remains unclear to what extent and how eating out helps or hinders people in achieving their dietary goals. The present study investigated how characteristics of the physical micro-environment in out-of-home food outlets (e.g., cafeterias, supermarkets, and restaurants) influence the healthiness of food choices among a sample of German adults with a goal to eat healthier. We used an experience sampling method to obtain detailed information about people's motivation for selecting a specific food outlet and the outlet's micro-environment. We further asked for people's mood, visceral state, and thoughts during their food choice and obtained evaluations of food choices reported near their occurrence and in externally valid conditions. The data was collected via a mobile app over a period of six to eleven days between November and December of 2018 in Germany with a sample of 409 participants (nobs = 6447). We find that even health-conscious people select food outlets and their respective micro-environments based on short-term goals, such as ease, taste, and speed of a consumption episode rather than long-term health outcomes. Using multiple regression, we show that micro-environments that promote healthy food, make such food more appealing and easier to select facilitate healthy food choices. We further identify some of the psychological mechanisms through which the micro-environment can affect food choices, as well as how individual characteristics moderate the relationship between specific micro-environmental factors and goal success. Taken together, our findings suggest the opportunity for, and arguably also necessity of, reshaping food environments to better facilitate healthier choices and support public health in the face of increasing out-of-home food consumption and the adverse consequences of unhealthy diets.

Associations of Sleep Duration and Screen Time with Incidence of Overweight in European Children: The IDEFICS/I.Family Cohort.

INTRODUCTION: Over the past decades, children have been increasingly using screen devices, while at the same time their sleep duration has decreased. Both behaviors have been associated with excess weight, and it is possible they act as mutually reinforcing behaviors for weight gain. The aim of the study was to explore independent, prospective associations of screen time and sleep duration with incident overweight in a sample of European children. METHODS: Data from 4,285 children of the IDEFICS/I.Family cohort who were followed up from 2009/2010 to 2013/2014 were analyzed. Hours per day of screen time and of sleep duration were reported by parents at baseline. Logistic regression analyses were carried out in separate and mutually adjusted models controlled for sex, age, European country region, parental level of education, and baseline BMI z-scores. RESULTS: Among normal weight children at baseline (N = 3,734), separate models suggest that every hour increase in screen time and every hour decrease in sleep duration were associated with higher odds of the child becoming overweight or obese at follow-up (OR = 1.16, 95% CI: 1.02-1.32 and OR = 1.23, 95% CI: 1.05-1.43, respectively). In the mutually adjusted model, both associations were attenuated slightly ( screen time OR = 1.13, 95% CI: 0.99-1.28; sleep duration OR = 1.20, 95% CI: 1.03-1.40), being consistently somewhat stronger for sleep duration. DISCUSSION/CONCLUSION: Both screen time and sleep duration increased the incidence of overweight or obesity by 13-20%. Interventions that include an emphasis on adequate sleep and minimal screen time are needed to establish their causal role in the prevention of overweight and obesity among European children.

Weight Status and BMI-Related Traits in Adolescent Friendship Groups and Role of Sociodemographic Factors: The European IDEFICS/I.Family Cohort.

BACKGROUND: During adolescence, health behaviors and weight status are increasingly influenced by friendship and peer networks. This paper examines resemblances in weight-related characteristics and how they differ by sociodemographic factors. METHODS: Over 3,000 friendships were reported by 1,603 adolescents, aged 11-16 years, who participated in the school-based I.Family study in 6 European countries. Each "source child" named 1-10 friends for whom standardized weight-related traits were available in the same survey. The mean value of the friends' traits weighted by time spent together was calculated, and related to the source child's trait. Country, age and sex of the source child, parental education, and immigrant background were considered for confounding and moderation. RESULTS: Source children's z-scores of body fat percent and BMI were positively associated with their friends' characteristics, in particular if they had highly educated parents. Positive associations were also found regarding the frequency of fast-food consumption, impulsivity, screen time, preference for sugar-sweetened foods, and hours spent in sports clubs, in increasing order of effect size. Additionally, correlations were observed between friends' cognitive and school functioning and being bullied. No associations were seen for a preference for high-fat foods, weight concerns, and health-related quality of life. Finally, parental education and immigrant background were associated between friends in all countries except Sweden, where no associations were observed. CONCLUSION: Adolescent friends shared a number of weight-related characteristics. For weight measures per se, positive associations with friends' characteristics were only observed in adolescents with high parental education. Associations regarding energy-balance behaviors and indicators of school-related well-being did not differ by parental education. Parental education and immigrant background correlated positively in friends in most countries showing that social aggregation is already occurring in adolescence. The wide spectrum of friendship associations in weight-related traits and behaviors suggests that health promotion initiatives in adolescents should be directed towards peer groups in both school-related and leisure-time environments. ISRCTN Registry: Pan-European IDEFICS/I.Family children cohort (ID ISRCTN62310987; https://doi.org/10.1186/ISRCTN62310987).

Social vulnerability as a predictor of physical activity and screen time in European children.

OBJECTIVES: To examine associations between social vulnerabilities and meeting physical activity (PA) and screen time (ST) recommendations during a 2-year follow-up. METHODS: 13,891 children aged 2.0 to  < 9.9 from eight European countries were assessed at baseline and 8482 children at follow-up. Children's sports club membership, PA and ST were collected via parental questionnaires. Moderate-to-vigorous physical activity (MVPA) was objectively assessed with accelerometers. Performing at least 1 h of MVPA daily and spending less than 2 h of ST defined physically active and non-sedentary children, respectively. Vulnerable groups were defined at baseline as children whose parents had minimal social networks, from non-traditional families, with migrant origin or with unemployed parents. Logistic mixed-effects analyses were performed adjusting for classical socioeconomic indicators. RESULTS: Children whose parents had minimal social networks had a higher risk of non-compliance with PA recommendations (subjectively assessed) at baseline. Migrants and children with unemployed parents had longer ST. All vulnerable groups were less likely to be sports club members. CONCLUSIONS: Migrants and children with unemployed parents are at risk for excessive ST and all vulnerable groups have lower odds of being sports club members.