The school food environment : associations with adolescent soft drink and snack consumption

Background
Because students may purchase food and drinks in and around their schools, the school food environment may be important for obesity-related eating behaviors such as soft drink and snack consumption. However, research exploring the associations between school environments and specific eating behaviors is sparse.

Methods
Associations of the availability of canteen food and drinks, the presence of food stores around schools, and individual cognitions (attitudes, norms, modeling, perceived behavioral control, and intentions) with soft drink and snack consumption were examined in a cross-sectional study (2005–2006) among 1293 adolescents aged 12–15 years. Soft drink and snack consumption and related cognitions were assessed with self-administered questionnaires. The presence of food stores and the distance to the nearest food store were calculated within a 500-meter buffer around each school. Data on the availability of soft drinks and snacks in school canteens were gathered by observation. In 2007, multilevel regression models were run to analyze associations and mediation pathways between cognitions, environmental factors, and behaviors.

Results
Adolescents' attitudes, subjective norms, parental and peer modeling, and intentions were positively associated with soft drink and snack consumption. There was an inverse association between the distance to the nearest store and the number of small food stores with soft drink consumption. These effects were mediated partly by cognitions.

Conclusions
This study provided little evidence for associations of environmental factors in the school environment with soft drink and snack consumption. Individual cognitions appeared to be stronger correlates of intake than physical school-environmental factors. Longitudinal research is needed to confirm these findings.

Family influences on children's physical activity and fruit and vegetable consumption

Background : There is evidence of a clustering of healthy dietary patterns and physical activity among young people and also of unhealthy behaviours. The identification of influences on children's health behaviors, particularly clustered health behaviors, at the time at which they develop is imperative for the design of interventions. This study examines associations between parental modelling and support and children's physical activity (PA) and consumption of fruit and vegetables (FV), and combinations of these behaviours.

Methods : In 2002/3 parents of 775 Australian children aged 10–12 years reported how frequently their child ate a variety of fruits and vegetables in the last week. Children wore accelerometers for eight days during waking hours. Parental modelling and parental support (financial and transport) were self-reported. Binary logistic and multinomial logistic regression analyses examined the likelihood of achieving ≥ 2 hours of PA per day (high PA) and of consuming ≥ 5 portions of FV per day (high FV) and combinations of these behaviors (e.g. high PA/low FV), according to parental modelling and support.

Results : Items of parental modelling and support were differentially associated with child behaviours. For example, girls whose parents reported high PA modelling had higher odds of consuming ≥ 5 portions of FV/day (OR = 1.95, 95% CI = 1.32–2.87, p < 0.001). Boys whose parents reported high financial support for snacks/fast foods had higher odds of having 'high PA/low FV' (OR = 2.0, 95% CI = 1.1–3.7).

Conclusion : Parental modelling of and support for physical activity and fruit and vegetable consumption were differentially associated with these behaviours in children across behavioural domains and with combinations of these behaviours. Promoting parents' own healthy eating and physical activity behaviours as well encouraging parental modelling and support of these behaviours in their children may be important strategies to test in future research.

Expanding the concept of parental control : a role for overt and covert control in children’s snacking behaviour?

The existing literature on parental control and children’s diets is confusing. The present paper reports two studies to explore an expanded conceptualisation of parental control with a focus on overt control which ‘can be detected by the child’ and covert control which ‘cannot be detected by the child’. In study 1, 297 parents of children aged between 4 and 11 completed a measure of overt control and covert control alongside ratings of their child’s snacking behaviour as a means to assess who uses either overt or covert control and how these aspects of parental control relate to a child’s snacking behaviour. The results showed that lighter parents and those with children perceived as heavier were more likely to use covert control and those from a higher social class were more likely to use overt control. Further, whilst greater covert control predicted a decreased intake of unhealthy snacks, greater overt control predicted an increased intake of healthy snacks. In study 2, 61 parents completed the same measure of overt and covert control alongside the three control subscales of the Child Feeding Questionnaire [Birch, L.L., Fisher, J.O., Grimm-Thomas, Markey, C.N., Sawyer, R. (2001). Confirmatory factor analysis of the Child Feeding Questionnaire: A measure of parental attitudes, beliefs and practices about child feeding and obesity proneness. Appetite, 36, 201–210] to assess degrees of overlap between these measures. The results showed that although these five measures of control were all positively correlated, the correlations between the new and existing measures indicated a maximum of 21% shared variance suggesting that covert and overt control are conceptually and statistically separate from existing measures of control. To conclude, overt and covert control may be a useful expansion of existing ways to measure and conceptualise parental control. Further, these constructs may differentially relate to snacking behaviour which may help to explain some of the confusion in the literature.

Can social cognitive theory constructs explain socio-economic variations in adolescent eating behaviours? A mediation analysis

Adolescents of low socio-economic position (SEP) are less likely than those of higher SEP to consume diets in line with current dietary recommendations. The reasons for these SEP variations remain poorly understood. We investigated the mechanisms underlying socio-economic variations in adolescents’ eating behaviours using a theoretically derived explanatory model. Data were obtained from a community-based sample of 2529 adolescents aged 12–15 years, from 37 secondary schools in Victoria, Australia. Adolescents completed a web-based survey assessing their eating behaviours, self-efficacy for healthy eating, perceived importance of nutrition and health, social modelling and support and the availability of foods in the home. Parents provided details of maternal education level, which was used as an indicator of SEP. All social cognitive constructs assessed mediated socio-economic variations in at least one indicator of adolescents’ diet. Cognitive factors were the strongest mediator of socio-economic variations in fruit intakes, while for energy-dense snack foods and fast foods, availability of energy-dense snacks at home tended to be strong mediators. Social cognitive theory provides a useful framework for understanding socio-economic variations in adolescent's diet and might guide public health programmes and policies focusing on improving adolescent nutrition among those experiencing socio-economic disadvantage.

Children's liking and wanting of snack products : influence of shape and flavour

Background : Children's food choices are guided by their preferences. However, these preferences may change due to repeated exposure.

Methods : This study investigated children's (n = 242, 7–12 yrs-old) liking and wanting for snacks over 3 weeks of daily consumption. The snacks differed in size (small vs large) or flavour (sweet vs sweet-sour). Two conditions were designed: 1) a monotonous group in which children continuously consumed the same snack across the 3 weeks, and 2) a free choice group in which children were allowed to freely choose amongst 3 different flavours of the snack each day during 3 weeks.

Results : Shape influenced long-term liking, i.e. small shaped snacks remained stable in liking over repeated consumption, whereas large shaped snacks with the same flavour decreased in liking. Mean wanting ratings for all snack products decreased over 3 weeks daily consumption. Flavour did not significantly influence liking and wanting over time. The ability to freely choose amongst different flavours tended to decrease children's liking (p < 0.1) and wanting (p < 0.001) for these products. Changes in liking rather than initial liking was the best predictor of snack choice during the intervention.

Conclusion : Wanting rather than liking was most affected by repeated daily consumption of snack foods over three weeks. In order to increase the likelihood that children will repeatedly eat a food product, smaller sized healthy snacks are preferred to larger sized snacks. Future research should focus on stabilizing wanting over repeated consumption.

Reducing obesity in early childhood : results from romp & chomp, an Australian community-wide intervention program

Background: There is growing evidence that community-based interventions can reduce childhood obesity in older children.
Objective: We aimed to determine the effectiveness of the Romp & Chomp intervention in reducing obesity and promoting healthy eating and active play in children aged 0–5 y.
Design: Romp & Chomp was a community-wide, multisetting, multistrategy intervention conducted in Australia from 2004 to 2008. The intervention occurred in a large regional city (Geelong) with a target group of 12,000 children and focused on community capacity building and environmental (political, sociocultural, and physical) changes to increase healthy eating and active play in early-childhood care and educational settings. The evaluation was repeat cross-sectional with a quasiexperimental design and comparison sample. Main outcome measures were body mass index (BMI), standardized BMI (zBMI; according to the Centers for Disease Control and Prevention 2000 reference charts), and prevalence of overweight/obesity and obesity-related behaviors in children aged 2 and 3.5 y.
Results: After the intervention there was a significantly lower mean weight, BMI, and zBMI in the 3.5-y-old subsample and a significantly lower prevalence of overweight/obesity in both the 2- and 3.5-y-old subsamples (by 2.5 and 3.4 percentage points, respectively) than in the comparison sample (a difference of 0.7 percentage points; P < 0.05) compared with baseline values. Intervention child-behavioral data showed a significantly lower intake of packaged snacks (by 0.23 serving), fruit juice (0.52 serving), and cordial (0.43 serving) than that in the comparison sample (all P < 0.05).
Conclusion: A community-wide multisetting, multistrategy intervention in early-childhood settings can reduce childhood obesity and improve young children's diets. This trial was registered with the Australian Clinical Trials Registry at anzctr.org.au as ACTRN12607000374460.

Does stress induce salt intake?

Psychological stress is a common feature of modern day societies, and contributes to the global burden of disease. It was proposed by Henry over 20 years ago that the salt intake of a society reflects the level of stress, and that stress, through its effect on increasing salt intake, is an important factor in the development of hypertension. This review evaluates the evidence from animal and human studies to determine if stress does induce a salt appetite and increase salt consumption in human subjects. Findings from animal studies suggest that stress may drive salt intake, with evidence for a potential mechanism via the sympatho-adrenal medullary system and/or the hypothalamo–pituitary–adrenal axis. In contrast, in the few laboratory studies conducted in human subjects, none has found that acute stress affects salt intake. However, one study demonstrated that life stress (chronic stress) was associated with increased consumption of snack foods, which included, but not specifically, highly salty snacks. Studies investigating the influence of chronic stress on eating behaviours are required, including consumption of salty foods. From the available evidence, we can conclude that in free-living, Na-replete individuals, consuming Na in excess of physiological requirements, stress is unlikely to be a major contributor to salt intake.

Parenting styles, family structure and adolescent dietary behaviour

Objective To examine associations between parenting styles, family structure and aspects of adolescent dietary behaviour.

Design Cross-sectional study.

Setting Secondary schools in the East Midlands, UK.

Subjects Adolescents aged 12–16 years (n 328, 57 % boys) completed an FFQ assessing their consumption of fruit, vegetables, unhealthy snacks and breakfast. Adolescents provided information on parental and sibling status and completed a seventeen-item instrument measuring the general parenting style dimensions of involvement and strictness, from which four styles were derived: indulgent, neglectful, authoritarian, authoritative.

Results After controlling for adolescent gender and age, analysis of covariance revealed no significant interactions between parenting style and family structure variables for any of the dietary behaviours assessed. Significant main effects for family structure were observed only for breakfast consumption, with adolescents from dual-parent families (P < 0·01) and those with no brothers (P < 0·05) eating breakfast on more days per week than those from single-parent families and those with one or more brother, respectively. Significant main effects for parenting style were observed for all dietary behaviours apart from vegetable consumption. Adolescents who described their parents as authoritative ate more fruit per day, fewer unhealthy snacks per day, and ate breakfast on more days per week than those who described their parents as neglectful.

Conclusions The positive associations between authoritative parenting style and adolescent dietary behaviour transcend family structure. Future research should be food-specific and assess the efficacy of strategies promoting the central attributes of an authoritative parenting style on the dietary behaviours of adolescents from a variety of family structures.

Trends in food intake in French children from 1999 to 2007 : results from the INCA (étude Individuelle Nationale des Consommations Alimentaires) dietary surveys

The objectives of the present study were to assess the intake of different food groups in French children aged 3–17 years (n 1455), and to analyse trends since a dietary survey undertaken 8 years ago. Dietary intake was evaluated using data from the 2006–7 cross-sectional INCA2 national dietary survey (étude Individuelle Nationale sur les Consommations Alimentaires), based on a 7 d food record. Dietary intake (percentage of subjects consuming the food group and amount eaten) was assessed for thirty-nine food categories. We observed variations in food consumption by age, sex, North–South regional gradient, seasonal period and educational level of the responding parent. Trends in dietary intake between 1999 and 2007 were determined by comparing the INCA1 (n 1126) and the INCA2 surveys. Both surveys had been carried out using the same methodology. The findings showed a decrease in energy intake in children aged 3–14 years, due to a reduction in the consumption of foods of animal origin and sweetened products. In adolescents aged 15–17 years, energy intake remained rather stable; during this 8-year period, the consumption of meat decreased, whereas the consumption of savoury snacks such as sandwiches and hamburgers significantly increased. These trends occurred during a time of growing concern about overweight and the associated co-morbidities in France. A number of public health measures were implemented over this period to improve dietary habits and physical activity patterns in children and adults. The periodic monitoring of dietary patterns through the INCA surveys is an essential part of the surveillance network in France.

Lay people's views of the school food supply

Purpose – This article aims to examine lay-persons' views of school food services in Victoria, Australia.

Design/methodology/approach – A cross-sectional postal questionnaire survey of a random sample of electors on the Electoral Roll in Victoria, Australia. Out of 1,000 potential respondents, 377 completed the questionnaire. Main outcome measures included responses to closed questions about foods supplied to children at school using five-point scales. Data analyses included frequency and cross-tabulation analyses, and multivariate analyses of principal component scores by demographic and personal values variables.

Findings – Many respondents were critical of children's school food services but they were generally supportive of food and health education, whilst holding ambivalent attitudes towards snacks and marketing practices.

Research limitations/implications – This was a cross-sectional survey with a relatively low response rate.

Practical implications – Understanding of laypersons' views of children's food services is likely to facilitate nutrition communication and promotion of healthy children's foods.

Originality/value – Lay views of children's food provision have rarely been reported, despite their importance for the support of public nutrition policies. The study identifies likely antecedents of lay people's views.

Associations between parental concern for adolescent weight and the home food environment and dietary intake

Objective: Examine associations between parental concern about adolescent weight and adolescent perceptions of their dietary intake, home food availability, family mealtime environment, and parents' feeding practices.

Design: Cross-sectional study.

Setting: Adolescents, aged 12-15 years from 37 secondary schools in Victoria, Australia, and their parents completed surveys in 2004-2005.

Participants: 1,448 adolescent–parent pairs.

Main Outcome Measures: Parental concern about adolescent weight; adolescent perceptions of their food intake and home food environment.

Analysis: Chi-square tests, exploratory factor analysis, independent t tests (P < .01).

Results: Although 12% of parents perceived their adolescent as overweight, 27% were concerned about their adolescent's weight (under- or overweight). Adolescents of concerned parents reported lower intakes of energy-dense snacks and less home availability of these food items, and they perceived that their parents less often listened to and considered their food preferences when shopping and cooking, than did adolescents of unconcerned parents. Concerned parents were no more likely to provide fruits and vegetables in the home or a positive family mealtime environment than unconcerned parents, at least as reported by their adolescents.

Conclusions and Implications: Parental concern about adolescent weight was associated with lower intakes of energy-dense snacks among adolescents, less home availability of these food items, and less supportive parental feeding practices. Parents should be encouraged to listen to and consider their adolescents' food preferences, and provide supportive family mealtime environments and healthful food in the home.

Reducing the energy density of multiple meals decreases the energy intake of preschool-age children1,2,3

Background: The energy density (ED) of an entrée affects children's energy intake at a meal consumed ad libitum. However, the effects in children of changing the ED of meals over multiple days are unknown.

Objective: We aimed to test the effect of reducing the ED of multiple meals on the ad libitum energy intake of preschool-age children over 2 d.

Design: In this crossover study, 3- to 5-y-old children (n = 10 boys, 16 girls) were served manipulated breakfasts, lunches, and afternoon snacks 2 d/wk for 2 wk. Foods and beverages served at these meals during 1 wk were lower in ED than were those served during the other week. ED reductions were achieved by decreasing fat and sugar and by increasing fruit and vegetables. Dinner and an evening snack were sent home with children, but these meals did not vary in ED. The same 2-d menu was served in both conditions.

Results: Children consumed a consistent weight of foods and beverages over 2 d in both conditions, and therefore their energy consumption declined by 389 ± 72 kcal (14%) in the lower-ED condition, a significant decrease (P < 0.0001). Differences in energy intake were significant at breakfast on day 1, and they accumulated at manipulated meals over 2 d (P < 0.01). Intake of the nonmanipulated meals was similar between conditions.

Conclusions: Children's energy intake is influenced by the ED of foods and beverages served over multiple days. These results strengthen the evidence that reducing the ED of the diet is an effective strategy for moderating children's energy intake.

Mediators of longitudinal associations between television viewing and eating behaviours in adolescents

Background: Television viewing has been associated with poor eating behaviours in adolescents. Changing unhealthy eating behaviours is most likely to be achieved by identifying and targeting factors shown to mediate the association between these behaviours. However, little is known about the mediators of the associations between television viewing and eating behaviours. The aim of this study was to examine mediators of the longitudinal associations between television viewing (TV) and eating behaviours among Australian adolescents.
Method: Eating behaviours were assessed using a web-based survey completed by a community-based sample of 1729 adolescents from years 7 and 9 of secondary schools in Victoria, Australia, at baseline (2004-2005) and two years later. TV viewing and the potential mediators (snacking while watching TV and perceived value of TV viewing) were assessed via the web-based survey at baseline.
Results: Adolescents who watched more than two hours of TV/day had higher intakes of energy-dense snacks and beverages, and lower intakes of fruit two years later. Furthermore, the associations between TV viewing and consumption of energy-dense snacks, energy-dense drinks and fruit were mediated by snacking while watching TV. Perceived value of TV viewing mediated the association between TV viewing and consumption of energy-dense snacks, beverages and fruit.
Conclusion: Snacking while watching TV and perceived value of TV viewing mediated the longitudinal association between TV viewing and eating behaviours among adolescents. The efficacy of methods to reduce TV viewing, change snacking habits while watching TV, and address the values that adolescents place on TV viewing should be examined in an effort to promote healthy eating among adolescents.

Association between food marketing exposure and adolescents' food choices and eating behaviors

The present study examined associations between food marketing exposure and adolescents’ food choices and reported consumption of energy-dense and nutrient-poor (EDNP) foods. A cross-sectional survey of 12,188 Australian secondary students aged 12–17 years was conducted, using a web-based self-report questionnaire. Measures included students’ level of exposure to commercial television and non-broadcast types of food marketing, whether they had tried a new product or requested a product they had seen advertised, and their reported consumption of fast food, sugary drinks and sweet and salty snacks. Results indicated greater exposure to commercial television, print/transport/school food marketing and digital food marketing were all independently associated with students’ food choices. High commercial television viewers (>2 h/day) were more likely to report higher consumption of EDNP foods (ORs ranged from 1.31 for fast food to 1.91 for sweet snacks). Some associations between digital food marketing exposure and students’ eating behaviors were found; however, print/transport/school food marketing was only related to sweet snack consumption. These study results suggest that cumulative exposure to television food advertising and other food marketing sources are positively linked to adolescents’ food choices and eating behaviors. Policy changes to restrict food marketing to young people should include both television and non-broadcast media.

Breastfeeding mothers consume more vegetables and a greater variety of fruits and vegetables than non-breastfeeding peers : the influence of socioeconomic position

Aim:  This study compared the diets of breastfeeding and non-breastfeeding mothers from socioeconomically diverse regions of Melbourne to determine whether breastfeeding is a marker for healthier maternal dietary intakes.

Methods:  This cross-sectional study obtained information via self-reported questionnaire from 529 first-time Melbourne mothers. Breastfeeding status was determined when the children were 3.9 months. Diet information was obtained using a validated Food Frequency Questionnaire. Maternal diet was assessed by seven indicators: average daily intake of fruit, vegetables, non-core drinks, non-core sweet snacks, non-core savoury snacks, variety of fruit and variety of vegetables eaten in the preceding 12 months. Associations between breastfeeding status and each dietary variable were assessed using linear regression analyses. Socioeconomic position, maternal body mass index and the cluster-based sampling design were controlled for.

Results:  Of the 529 subjects, 70% were breastfeeding their child. Compared with non-breastfeeding mothers, breastfeeding mothers were found to consume more serves of vegetables (P= 0.001), a greater variety of fruit and vegetables (P= 0.001 and P≤ 0.001 respectively), and sweet snacks were consumed more frequently (P= 0.006). Differences were observed between low and high socioeconomic position mothers for fruit serves (P= 0.003), vegetable serves (P= 0.010) and fruit variety (P= 0.006). These associations persisted after controlling for socioeconomic position and maternal body mass index.

Conclusions:  The association between infant feeding (breastfeeding) and some aspects of maternal diet provides further evidence suggesting a link between maternal and child diets from a younger age than previously examined.