Socio-economic disparities in Australian adolescents' eating behaviours

Objective: To assess the association between socio-economic position (SEP) and poor eating behaviours in a large representative sample of Australian secondary school students.
Design: Cross-sectional survey of students’ vegetable, fruit, sugar-sweetened beverage and fast-food consumption assessed using validated instruments and collected via a web-based self-report format.
Setting: Secondary schools across all Australian states and territories.
Subjects: Secondary-school students (n 12 188; response rate: 54 %) aged 12–17 years participating in the 2009–10 National Secondary Students’ Diet and Activity (NaSSDA) survey.
Results: Overall, 25% of students reported consuming <1 serving of vegetables/d and 29% reported eating <1 serving of fruit/d. Fourteen per cent of students reported drinking at least 1–2 cups of sugar-sweetened beverages/d while 9% reported eating fast food <3 times/week. After adjusting for other demographic factors, students of lower-SEP areas were more likely to report low intake of vegetables (F (4, 231) = 3.61, P = 0.007) and high frequency of consumption of sugar-sweetened beverages (F (4, 231) =8.41, P < 0.001) and fast food (F (4, 231) = 4.59, P =0.001) compared with students of high-SEP neighbourhoods. A positive SEP association was found for fruit consumption among female students only (F (4, 231) = 4.20, P = 0.003). Those from lower-SEP areas were also more likely to engage in multiple poor eating behaviours (F (4, 231) = 5.80, P, < 0.001).
Conclusions: Results suggest that socio-economic disparities in Australian adolescents’ eating behaviours do exist, with students residing in lower-SEP neighbourhoods faring less well than those from high-SEP neighbourhoods. Reducing social inequalities in eating behaviours among young people should be a key consideration of future preventive strategies.

Cost effectiveness of childhood obesity interventions: Evidence and methods for CHOICES

INTRODUCTION: The childhood obesity epidemic continues in the U.S., and fiscal crises are leading policymakers to ask not only whether an intervention works but also whether it offers value for money. However, cost-effectiveness analyses have been limited. This paper discusses methods and outcomes of four childhood obesity interventions: (1) sugar-sweetened beverage excise tax (SSB); (2) eliminating tax subsidy of TV advertising to children (TV AD); (3) early care and education policy change (ECE); and (4) active physical education (Active PE). METHODS: Cost-effectiveness models of nationwide implementation of interventions were estimated for a simulated cohort representative of the 2015 U.S. population over 10 years (2015-2025). A societal perspective was used; future outcomes were discounted at 3%. Data were analyzed in 2014. Effectiveness, implementation, and equity issues were reviewed. RESULTS: Population reach varied widely, and cost per BMI change ranged from $1.16 (TV AD) to $401 (Active PE). At 10 years, assuming maintenance of the intervention effect, three interventions would save net costs, with SSB and TV AD saving $55 and $38 for every dollar spent. The SSB intervention would avert disability-adjusted life years, and both SSB and TV AD would increase quality-adjusted life years. Both SSB ($12.5 billion) and TV AD ($80 million) would produce yearly tax revenue. CONCLUSIONS: The cost effectiveness of these preventive interventions is greater than that seen for published clinical interventions to treat obesity. Cost-effectiveness evaluations of childhood obesity interventions can provide decision makers with information demonstrating best value for the money.

Health literacy and the determinants of obesity: a population-based survey of sixth grade school children in Taiwan

BACKGROUND: Health literacy has become an important health policy and health promotion agenda item in recent years. It had been seen as a means to reduce health disparities and a critical empowerment strategy to increase people's control over their health. So far, most of health literacy studies mainly focus on adults with few studies investigating associations between child health literacy and health status. This study aimed to investigate the association between health literacy and body weight in Taiwan's sixth grade school children.

METHODS: Using a population-based survey, 162,209 sixth grade (11-12 years old) school children were assessed. The response rate at school level was 83%, with 70% of all students completing the survey. The Taiwan child health literacy assessment tool was applied and information on sex, ethnicity, self-reported health, and health behaviors were also collected. BMI was used to classify the children as underweight, normal, overweight, or obese. A multinomial logit model with robust estimation was used to explore associations between health literacy and the body weight with an adjustment for covariates.

RESULTS: The sample consisted of 48.9% girls, 3.8% were indigenous and the mean BMI was 19.55 (SD = 3.93). About 6% of children self-reported bad or very bad health. The mean child health literacy score was 24.03 (SD = 6.12, scale range from 0 to 32). The overall proportion of obese children was 15.2%. Children in the highest health literacy quartile were less likely to be obese (12.4%) compared with the lowest quartile (17.4%). After controlling for gender, ethnicity, self-rated health, and health behaviors, children with higher health literacy were less likely to be obese (Relative Risk Ratio (RRR) = 0.94, p < 0.001) and underweight (RRR = 0.83, p < 0.001). Those who did not have regular physical activity, or had sugar-sweetened beverage intake (RRR > 1.10, p < 0.0001) were more likely to report being overweight or obese.

CONCLUSIONS: This study demonstrates strong links between health literacy and obesity, even after adjusting for key potential confounders, and provides new insights into potential intervention points in school education for obesity prevention. Systematic approaches to integrating a health literacy curriculum into schools may mitigate the growing burden of disease due to obesity.

A school-based intervention incorporating smartphone technology to improve health-related fitness among adolescents : rationale and study protocol for the NEAT and ATLAS 2.0 cluster randomised controlled trial and dissemination study

INTRODUCTION: Physical inactivity has been described as a global pandemic. Interventions aimed at developing skills in lifelong physical activities may provide the foundation for an active lifestyle into adulthood. In general, school-based physical activity interventions targeting adolescents have produced modest results and few have been designed to be 'scaled-up' and disseminated. This study aims to: (1) assess the effectiveness of two physical activity promotion programmes (ie, NEAT and ATLAS) that have been modified for scalability; and (2) evaluate the dissemination of these programmes throughout government funded secondary schools. METHODS AND ANALYSIS: The study will be conducted in two phases. In the first phase (cluster randomised controlled trial), 16 schools will be randomly allocated to the intervention or a usual care control condition. In the second phase, the Reach, Effectiveness, Adoption, Implementation and Maintenance (Re-AIM) framework will be used to guide the design and evaluation of programme dissemination throughout New South Wales (NSW), Australia. In both phases, teachers will be trained to deliver the NEAT and ATLAS programmes, which will include: (1) interactive student seminars; (2) structured physical activity programmes; (3) lunch-time fitness sessions; and (4) web-based smartphone apps. In the cluster RCT, study outcomes will be assessed at baseline, 6 months (primary end point) and 12-months. Muscular fitness will be the primary outcome and secondary outcomes will include: objectively measured body composition, cardiorespiratory fitness, flexibility, resistance training skill competency, physical activity, self-reported recreational screen-time, sleep, sugar-sweetened beverage and junk food snack consumption, self-esteem and well-being.

Mediating effects of dietary intake on associations of TV viewing, body mass index and metabolic syndrome in adolescents

OBJECTIVE: Evidence suggests that TV viewing is associated with body mass index (BMI) and metabolic syndrome (MetS) in adolescents. However, it is unclear whether dietary intake mediates these relationships.

METHODS: A cross-sectional analysis was conducted in adolescents (12-19 years) participating in the 2003-2006 United States National Health and Nutrition Examination Survey. BMI z scores (zBMI) (n = 3,161) and MetS (n = 1,379) were calculated using age- and sex-specific criteria for adolescents. TV viewing (h/day) was measured via a self-reported questionnaire, and dietary intake was assessed using two 24-h recalls. Using the MacKinnon method, a series of mediation analyses were conducted examining five dietary mediators (total energy intake, fruit and vegetable intake, discretionary snacks, sugar-sweetened beverages and diet quality) of the relationships between TV viewing and zBMI and MetS.

RESULTS: Small positive relationships were observed between TV viewing and zBMI (β = 0.99, p < 0.001) and TV viewing and MetS (OR = 1.18, p = 0.046). No dietary element appeared to mediate the relationship between TV viewing and zBMI. However, sugar-sweetened beverage consumption and fruit and vegetable intake partially mediated the relationship between TV viewing and MetS, explaining 8.7% and 4.1% of the relationship, respectively.

CONCLUSIONS: These findings highlight the complexity of the relationships between TV viewing, dietary intake and cardiometabolic health outcomes, and that TV viewing should remain a target for interventions.

Dietary sodium intake and overweight and obesity in children and adults: a protocol for a systematic review and meta-analysis.

BACKGROUND: Overweight and obesity in children and adults is a major public health concern. Emerging evidence suggests dietary sodium intake may be associated with obesity. This systematic review and meta-analysis will aim to (i) assess the relation between dietary sodium intake and measures of adiposity in children and adults and (ii) examine the relation between sodium intake and sugar-sweetened beverage (SSB) consumption, which is a known risk factor for obesity. METHODS/DESIGN: An electronic search will be conducted using Medline Complete, CINAHL, Scopus, Embase and Cochrane central register of controlled trials (CENTRAL). The search strategy will identify published peer-reviewed articles that report on dietary sodium and either a marker of adiposity or SSB consumption. Only human studies (ages >1 year) in English will be included, and no limits will be placed on publication date. No restrictions will be placed on the method of sodium intake assessment. Cross-sectional, prospective studies, and randomised controlled trials with a duration of ≥ 3 months will be included. Studies with participants with renal disease, cancer, type 1 diabetes or heart failure or who are pregnant will be excluded. To assess the quality of studies, the Cochrane's Collaboration tool for assessing risk of bias in randomised trials will be used for randomised controlled trials (RCTs), and the modified Newcastle-Ottawa Scale will be used for cross-sectional and prospective studies. Meta-analysis will be used to assess the relation of sodium intake with two primary outcomes: (i) BMI and body weight in adults and BMI z-score in children and (ii) weight category (i.e. healthy weight vs. overweight/obese). For any outcomes in which meta-analysis is not possible, we will present data as a systematic review. Findings will be grouped and reported separately for children and adolescents (ages 1-17 years) and adults (ages >18 years). DISCUSSION: This review and meta-analysis will provide insight into the relation between dietary sodium intake and overweight and obesity. This information can be used to inform public health policies which target population sodium consumption.

Supermarket Healthy Eating for Life (SHELf): protocol of a randomised controlled trial promoting healthy food and beverage consumption through price reduction and skill-building strategies

Background: In the context of rising food prices, there is a need for evidence on the most effective approaches for promoting healthy eating. Individually-targeted behavioural interventions for increasing food-related skills show promise, but are unlikely to be effective in the absence of structural supports. Fiscal policies have been advocated as a means of promoting healthy eating and reducing obesity and nutrition-related disease, but there is little empirical evidence of their effectiveness. This paper describes the Supermarket Healthy Eating for LiFe (SHELf) study, a randomised controlled trial to investigate effectiveness and cost-effectiveness of a tailored skill-building intervention and a price reduction intervention, separately and in combination, against a control condition for promoting purchase and consumption of healthy foods and beverages in women from high and low socioeconomic groups.
Methods/design: SHELf comprises a randomised controlled trial design, with participants randomised to receive either (1) a skill-building intervention; (2) price reductions on fruits, vegetables and low-joule soft drink beverages and water; (3) a combination of skill-building and price reductions; or (4) a control condition. Five hundred women from high and low socioeconomic areas will be recruited through a store loyalty card program and local media. Randomisation will occur on receipt of informed consent and baseline questionnaire. An economic evaluation from a societal perspective using a cost-consequences approach will compare the costs and outcomes between intervention and control groups.
Discussion: This study will build on a pivotal partnership with a major national supermarket chain and the Heart Foundation to investigate the effectiveness of intervention strategies aimed at increasing women’s purchasing and consumption of fruits and vegetables and decreased purchasing and consumption of sugar-sweetened beverages. It will be among the first internationally to examine the effects of two promising approaches - skill-building and price reductions - on diet amongst women.

Monitoring food and non-alcoholic beverage promotions to children

Food and non-alcoholic beverage marketing is recognized as an important factor influencing food choices related to non-communicable diseases. The monitoring of populations' exposure to food and non-alcoholic beverage promotions, and the content of these promotions, is necessary to generate evidence to understand the extent of the problem, and to determine appropriate and effective policy responses. A review of studies measuring the nature and extent of exposure to food promotions was conducted to identify approaches to monitoring food promotions via dominant media platforms. A step-wise approach, comprising ‘minimal’, ‘expanded’ and ‘optimal’ monitoring activities, was designed. This approach can be used to assess the frequency and level of exposure of population groups (especially children) to food promotions, the persuasive power of techniques used in promotional communications (power of promotions) and the nutritional composition of promoted food products. Detailed procedures for data sampling, data collection and data analysis for a range of media types are presented, as well as quantifiable measurement indicators for assessing exposure to and power of food and non-alcoholic beverage promotions. The proposed framework supports the development of a consistent system for monitoring food and non-alcoholic beverage promotions for comparison between countries and over time.

Stores healthy options project in remote indigenous communities (SHOP@RIC): a protocol of a randomised trial promoting healthy food and beverage purchases through price discounts and in-store nutrition education

Background
Indigenous Australians suffer a disproportionate burden of preventable chronic disease compared to their non-Indigenous counterparts – much of it diet-related. Increasing fruit and vegetable intakes and reducing sugar-sweetened soft-drink consumption can reduce the risk of preventable chronic disease. There is evidence from some general population studies that subsidising healthier foods can modify dietary behaviour. There is little such evidence relating specifically to socio-economically disadvantaged populations, even though dietary behaviour in such populations is arguably more likely to be susceptible to such interventions.

This study aims to assess the impact and cost-effectiveness of a price discount intervention with or without an in-store nutrition education intervention on purchases of fruit, vegetables, water and diet soft-drinks among remote Indigenous communities.

Methods/Design
We will utilise a randomised multiple baseline (stepped wedge) design involving 20 communities in remote Indigenous Australia. The study will be conducted in partnership with two store associations and twenty Indigenous store boards. Communities will be randomised to either i) a 20% price discount on fruit, vegetables, water and diet soft-drinks; or ii) a combined price discount and in-store nutrition education strategy. These interventions will be initiated, at one of five possible time-points, spaced two-months apart. Weekly point-of-sale data will be collected from each community store before, during, and for six months after the six-month intervention period to measure impact on purchasing of discounted food and drinks. Data on physical, social and economic factors influencing weekly store sales will be collected in order to identify important covariates. Intervention fidelity and mediators of behaviour change will also be assessed.

Discussion
This study will provide original evidence on the effectiveness and cost-effectiveness of price discounts with or without an in-store nutrition education intervention on food and drink purchasing among a socio-economically disadvantaged population in a real-life setting.

Australian children's consumption of caffeinated, formulated beverages: a cross-sectional analysis

BACKGROUND: Caffeine is a common additive in formulated beverages, including sugar-sweetened beverages. Currently there are no data on the consumption of caffeinated formulated beverages in Australian children and adolescents. This study aimed to determine total intake and consumption patterns of CFBs in a nationally representative sample of Australian children aged 2-16 years and to determine contribution of CFBs to total caffeine intake. Consumption by day type, mealtime and location was also examined.

METHODS: Dietary data from one 24-hour recall collected in the 2007 Australian National Children's Nutrition and Physical Activity Survey were analysed. CFBs were defined as beverages to which caffeine has been added as an additive, including cola-type beverages and energy drinks. Socioeconomic status was based on the highest level of education attained by the participant's primary caregiver. Time of day of consumption was classified based on traditional mealtimes and type of day of consumption as either a school or non-school day. Location of consumption was defined by the participant during the survey.

RESULTS: On the day of the survey 15% (n = 642) of participants consumed CFBs. Older children and those of low socioeconomic background were more likely to consume CFBs (both P < 0.001). Amongst the 642 consumers mean (95% CI) intakes were 151 (115-187)g/day, 287 (252-321)g/day, 442 (400-484)g/day, and 555 (507-602)g/day for 2-3, 4-8, 9-13 and 14-16 year olds respectively. Consumers of CFBs had higher intakes of caffeine (mean (95% CI) 61 (55-67)mg vs. 11 (10-12)mg) and energy (mean (95% CI) 9,612 (9,247-9978)kJ vs. 8,186 (8,040-8,335)kJ) than non-consumers (both P < 0.001). CFBs contributed 69% of total daily caffeine intake. CFB intake was higher on non-school days compared with school days (P < 0.005) and consumption occurred predominantly at the place of residence (56%), within the "dinner" time bracket (17:00-20:30, 44%).

CONCLUSIONS: The consumption of CFBs by all age groups within Australian children is of concern. Modifications to the permissibility of caffeine as a food additive may be an appropriate strategy to reduce the intake of caffeine in this age group. Additional areas for intervention include targeting parental influences over mealtime beverage choices.

Modeling the cost effectiveness of child care policy changes in the U.S.

INTRODUCTION: Child care facilities influence diet and physical activity, making them ideal obesity prevention settings. The purpose of this study is to quantify the health and economic impacts of a multi-component regulatory obesity policy intervention in licensed U.S. child care facilities. METHODS: Two-year costs and BMI changes resulting from changes in beverage, physical activity, and screen time regulations affecting a cohort of up to 6.5 million preschool-aged children attending child care facilities were estimated in 2014 using published data. A Markov cohort model simulated the intervention's impact on changes in the U.S. population from 2015 to 2025, including short-term BMI effects and 10-year healthcare expenditures. Future outcomes were discounted at 3% annually. Probabilistic sensitivity analyses simulated 95% uncertainty intervals (UIs) around outcomes. RESULTS: Regulatory changes would lead children to watch less TV, get more minutes of moderate and vigorous physical activity, and consume fewer sugar-sweetened beverages. Within the 6.5 million eligible population, national implementation could reach 3.69 million children, cost $4.82 million in the first year, and result in 0.0186 fewer BMI units (95% UI=0.00592 kg/m(2), 0.0434 kg/m(2)) per eligible child at a cost of $57.80 per BMI unit avoided. Over 10 years, these effects would result in net healthcare cost savings of $51.6 (95% UI=$14.2, $134) million. The intervention is 94.7% likely to be cost saving by 2025. CONCLUSIONS: Changing child care regulations could have a small but meaningful impact on short-term BMI at low cost. If effects are maintained for 10 years, obesity-related healthcare cost savings are likely.

24-h urinary sodium excretion is associated with obesity in a cross-sectional sample of Australian schoolchildren

Emerging evidence indicates that dietary Na may be linked to obesity; however it is unclear whether this relationship is independent of energy intake (EI). The aim of this study was to assess the association between Na intake and measures of adiposity, including BMI z score, weight category and waist:height ratio (WHtR), in a sample of Australian schoolchildren. This was a cross-sectional study of schoolchildren aged 4-12 years. Na intake was assessed via one 24-h urine collection. BMI was converted to age- and sex-specific z scores, and WHtR was used to define abdominal obesity. In children aged ≥8 years, EI was determined via one 24-h dietary recall. Of the 666 children with valid urine samples 55 % were male (average age 9·3 (sd 1·8) years). In adjusted models an additional 17 mmol/d of Na was associated with a 0·10 higher BMI z score (95 % CI 0·07, 0·13), a 23 % (OR 1·23; 95 % CI 1·16, 1·31) greater risk of being overweight/obese and a 15 % (OR 1·15; 95 % CI 1·09, 1·23) greater risk of being centrally obese. In the subsample of 8-12-year-old children (n 458), adjustment for EI did not markedly alter the associations between Na and adiposity outcomes. Using a robust measure of daily Na intake we found a positive association between Na intake and obesity risk in Australian schoolchildren, which could not be explained by total energy consumption. To determine whether this is a causal relationship, longitudinal studies, with high-quality measures of Na and EI, are required.

Diet, nutrition and the prevention of excess weight gain and obesity

Objective: To review the evidence on the diet and nutrition causes of obesity and to recommend strategies to reduce obesity prevalence.
Design: The evidence for potential aetiological factors and strategies to reduce obesity prevalence was reviewed, and recommendations for public health action, population nutrition goals and further research were made.
Results: Protective factors against obesity were considered to be: regular physical activity (convincing); a high intake of dietary non-starch polysaccharides (NSP)/fibre (convincing); supportive home and school environments for children (probable); and breastfeeding (probable). Risk factors for obesity were considered to be sedentary lifestyles (convincing); a high intake of energy-dense, micronutrient-poor foods (convincing); heavy marketing of energy-dense foods and fast food outlets (probable); sugar-sweetened soft drinks and fruit juices (probable); adverse social and economic conditions—developed countries, especially in women (probable).
A broad range of strategies were recommended to reduce obesity prevalence including: influencing the food supply to make healthy choices easier; reducing the marketing of energy dense foods and beverages to children; influencing urban environments and transport systems to promote physical activity; developing community-wide programmes in multiple settings; increased communications about healthy eating and physical activity; and improved health services to promote breastfeeding and manage currently overweight or obese people.
Conclusions: The increasing prevalence of obesity is a major health threat in both low- and high income countries. Comprehensive programmes will be needed to turn the epidemic around.

Dose-response associations between screen time and overweight among youth

Objective. To examine dose-response associations between screen time and overweight, independent of physical activity and dietary intake.

Methods. Participants were 580 Dutch youth (13 years; 48% boys). Body mass index, waist circumference and skinfold thickness at four sites determined weight status. Questionnaires examined television viewing and computer use, participation in organized sport and high caloric snack and sugar-containing beverage consumption.

Results. There were no significant associations among boys. Compared with girls spending less than two hours/day in screen time, those who spent three to four hours/day were more likely to be classified as overweight by waist circumference (odds ratio [OR]=3.4; 95% confidence intervals [CI]=1.1-10.7; p=0.03), and this likelihood increased substantially among those spending more than four hours/day (OR=5.5; 95% CI=2.1-14.1; p≤0.0001).

Conclusions. Girls who spend three or more hours/day in screen time are at increased risk of being classified as overweight by waist circumference.