Family food environments as determinants of preschool-aged children`s eating behaviours: implications for obesity prevention policy. A review.

Children's eating behaviours are fundamental to their health. Dietary surveys indicate that children's food consumption is likely to promote a range of diet-related diseases, including overweight and obesity, which are associated with a range of psychosocial and physical disorders. With the prevalence of overweight and obesity rapidly increasing, opportunities for informed prevention have become a focus of strategy. Diet is recognised as important in the genesis of obesity. We present data that demonstrate that eating behaviours are likely to be established early in life and may be maintained into adulthood. We review literature that shows that children's eating behaviours are influenced by the family food environment. These findings suggest that the family environment should be considered in developing obesity prevention strategy for children, yet the current strategy focuses primarily on the school environment. Those factors in the family environment that appear to be important include: parental food preferences and beliefs, children's food exposure; role modelling; media exposure; and child-parent interactions around food. However, the existing data are based on small scale and unrepresentative US samples. At a population level, we have few insights regarding family food environments and consequently little information about how such environments influence children's eating behaviours and thus their risk for obesity. We suggest research that may promote a better understanding of the role of family food environments as determinants of children's eating behaviour, and consider the implications for obesity prevention in Australia. (Aust J Nutr Diet 2001;58:19-25)

Evidence-based development of school-based and family-involved prevention of overweight across Europe : the ENERGY-project's design and conceptual framework

Background
There is an urgent need for more carefully developed public health measures in order to curb the obesity epidemic among youth. The overall aim of the "EuropeaN Energy balance Research to prevent excessive weight Gain among Youth" (ENERGY)-project is the development and formative evaluation of a theory-informed and evidence-based multi-component school-based and family-involved intervention program ready to be implemented and evaluated for effectiveness across Europe. This program aims at promoting the adoption or continuation of health behaviors that contribute to a healthy energy balance among school-aged children. Earlier studies have indicated that school and family environments are key determinants of energy-balance behaviors in schoolchildren. Schools are an important setting for health promotion in this age group, but school-based interventions mostly fail to target and involve the family environment.

Methods
Led by a multidisciplinary team of researchers from eleven European countries and supported by a team of Australian experts, the ENERGY-project is informed by the Environmental Research Framework for Weight gain Prevention, and comprises a comprehensive epidemiological analysis including 1) systematic reviews of the literature, 2) secondary analyses of existing data, 3) focus group research, and 4) a cross European school-based survey.

Results and discussion
The theoretical framework and the epidemiological analysis will subsequently inform stepwise intervention development targeting the most relevant energy balance-related behaviors and their personal, family-environmental and school-environmental determinants applying the Intervention Mapping protocol. The intervention scheme will undergo formative and pilot evaluation in five countries. The results of ENERGY will be disseminated among key stakeholders including researchers, policy makers and the general population.

Conclusions
The ENERGY-project is an international, multidisciplinary effort to develop and test an evidence-based and theory-informed intervention program for obesity prevention among school-aged children.

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.

Behavioural determinants of the obesity epidemic

Obesity is a serious and growing public health problem affecting developed and developing countries. It is generally agreed that the causes of the current obesity epidemic are not genetic in origin, but are the result of changes in the environments in which we live. While acknowledging the importance of environmental factors, the central role of behaviour in the obesity epidemic cannot be ignored. It is our eating, physical activity and sedentary behaviours that form the interface between our biology and the environments to which we are exposed. However, a lack of understanding of the specific behaviours that are important in the aetiology of obesity poses a major constraint to preventing obesity. A better understanding of the behaviours that contribute to weight gain and obesity is critical in order to plan and implement effective obesity prevention initiatives.Theory-driven investigations of eating, physical activity and sedentary behaviours, their determinants, and their role in weight gain and obesity among different population groups are urgent research priorities. Without an understanding of the key behaviours that contribute to weight gain, and the influences on these behaviours, it will remain difficult to identify where to intervene in the environment and be confident that action will prevent obesity.

An ecological study of the relationship between social and environmental determinants of obesity

There is growing concern with the increasing prevalence of obesity in industrialised countries, a trend that is more apparent in the poor than in the rich. In an ecological study, the relationship between an area measure of socioeconomic status (SES) and the density of fast-food outlets was examined as one possible explanation for the phenomenon. It was found that there was a dose-response between SES and the density of fast-food outlets, with people living in areas from the poorest SES category having 2.5 times the exposure to outlets than people in the wealthiest category. The findings are discussed.

Re-gendering labour: class and gender determinants of New South Wales electoral behaviour 1930-32

Historians have neglected tbe impact of female enfranchisement on Australian electoral outcomes. This papers employs multivariate analysis to explore electoral behaviour in New South Wales during the Great Depression. It argues that women were less prone to support Labor than men, but that women in paid employment constituted a partial exception to this pattern. In 1932 the conservative parties significantly eroded Labor's working-class support. Part of this success was due to the ability of employers to coerce workers with the threat of dismissal. Female wage earners were particularly vulnerable to this coercion. Conservative electoral appeals recast masculinity in terms of family responsibility rather than class assertion. Conflict in the household economy possibly influenced women to vote against Labor due to its identification with the cause of male breadwinners. Overall female voting behaviour was more stable than that of men and this despite the higb profile of issues that would have been expected particularly to influence female voters.

People, places...and other people? Integrating understanding of intrapersonal, social and environmental determinants of physical activity

“People or places: what should be the target?” was the provocative title of a keynote session at the fifth Australian National Physical Activity Conference held in Melbourne in 2005. This paper will argue that in fact there need not be major conflict between these views, and that couching recent debate about physical activity promotion as a polarised choice between these presents a false dichotomy. To illustrate this, the paper will consider several problems with singular approaches to understanding and promoting physical activity, and will then describe emerging empirical evidence on the nexus between people and places. To balance an increasing emphasis in the scientific literature on physical environmental determinants of physical activity, the role of intrapersonal and social factors will also be revisited. It is concluded that growing evidence supporting the multiple domains of influence on physical activity justifies calls for multi-disciplinary and multi-sectoral partnerships and approaches to the promotion of active lifestyles.

Individual, social and home environment determinants of change in children's television viewing: the Switch-Play intervention

Understanding potential determinants of change in television (TV) viewing among children may enhance the effectiveness of programs targeting this behaviour. This study aimed to investigate the contribution of individual, social and home environment factors among 10-year-old Australian children to change in TV viewing over a 21-month period. A total of 164 children (49% boys) completed a 19-lesson (9-month) intervention program to reduce TV viewing time. Children completed self-administered surveys four times over 21 months (pre- and post-intervention, 6- and 12-month follow-up). Baseline factors associated with change in TV viewing during the intervention and follow-up periods were: ‘asking parents ≥once/week to switch off the TV and play with them’ (21.6 min/day more than those reporting <once/week, p = 0.007); being able to ‘watch just 1 h of TV per day’ (26.1 min/day less than those who could not, p = 0.010); ‘watching TV no matter what was on’ (36.6 min/day more than those who did not, p < 0.001); and ‘continuing to watch TV after their program was over’ (33.0 min/day more than those who did not, p = 0.006). With every unit increase in baseline frequency of TV viewing with family and friends, children spent on average 4.0 min/day more watching TV over the 21-month period (p = 0.047). Baseline number and placement of TVs at home did not predict change in children's TV viewing over the 21 months. Greater understanding of the family dynamics and circumstances, as well as the individual and social determinants of TV viewing, will be required if we are to develop effective strategies for reducing TV viewing in children.

On the determinants of derivative usage by Australian companies

This paper provides an examination of the determinants of derivative use by Australian corporations. We analysed the characteristics of a sample of 469 firm/year observations drawn from the largest Australian publicly listed companies in 1999 and 2000 to address two issues: the decision to use financial derivatives and the extent to which they are used. Logit analysis suggests that a firm's leverage (distress proxy), size (financial distress and setup costs) and liquidity (financial constraints proxy) are important factors associated with the decision to use derivatives. These findings support the financial distress hypothesis while the evidence on the underinvestment hypothesis is mixed. Additionally, setup costs appear to be important, as larger firms are more likely to use derivatives. Tobit results, on the other hand, show that once the decision to use derivatives has been made, a firm uses more derivatives as its leverage increases and as it pays out more dividends (hedging substitute proxy). The overall results indicate that Australian companies use derivatives with a view to enhancing the firms' value rather than to maximizing managerial wealth. In particular, corporations' derivative policies are mostly concerned with reducing the expected cost of financial distress and managing cash flows. Our inability to identify managerial influences behind the derivative decision suggests a competitive Australian managerial labor market.

Determinants of bone density in 30- to 65-year-old women: A co-twin study

Introduction: Reported effects of body composition and lifestyle of bone mineral density in pre-elderly adult women have been inconsistent.

Methods: In a co-twin study of 146 female twin pairs aged 30 to 65 years, DXA was used to measure bone mineral density at the lumbar spine, total hip, and forearm, total body bone mineral content, and lean and fat mass. Height and weight were measured. Menopausal status, dietary calcium intake, physical activity, current tobacco use, and alcohol consumption were determined by questionnaire. Within-pair differences in bone measures were regressed through the origin against within-pair differences in putative determinants.

Results: Lean mass and fat mass were associated with greater bone mass at all sites. A discordance of 10 pack-years smoking was related to a 2.3-3.3% (SE, 0.8-1.0) decrease in bone density at all sites except the forearm, with the effects more evident in postmenopausal women. In all women, a 0.8% (SE, 0.3) difference in hip bone mineral density was associated with each hour per week difference in sporting activity, with effects more evident in premenopausal women. Daily dietary calcium intake was related to total body bone mineral content and forearm bone mineral density (1.4 ± 0.7% increase for every 1000 mg). Lifetime alcohol consumption and walking were not consistently related to bone mass.

Conclusion: Several lifestyle and dietary factors, in particular tobacco use, were related to bone mineral density. Effect sizes varied by site. Characterization of determinants of bone mineral density in midlife and thereafter may lead to interventions that could minimize postmenopausal bone loss and reduce osteoporotic fracture risk.

Health-related quality of life of overweight and obese children

Context: The negative effects of childhood overweight and obesity on quality of life (QOL) have been shown in clinical samples but not yet in population-based community samples.

Objective: To determine relationships between weight and health-related QOL reported by parent-proxy and child self-report in a population sample of elementary school children.

Design, Setting, and Participants: Cross-sectional data collected in 2000 within the Health of Young Victorians Study, a longitudinal cohort study commenced in 1997. Individuals were recruited via a random 2-stage sampling design from primary schools in Victoria, Australia. Of the 1943 children in the original cohort, 1569 (80.8%) were resurveyed 3 years later at a mean age of 10.4 years.

Main Outcome Measures: Health-related QOL using the PedsQL 4.0 survey completed by both parent-proxy and by child self-report. Summary scores for children'S total, physical, and psychosocial health and subscale scores for emotional, social, and school functioning were compared by weight category based on International Obesity Task Force cut points.

Results: Of 1456 participants, 1099 (75.5%) children were classified as not overweight; 294 (20.2%) overweight; and 63 (4.3%) obese. Parent-proxy and child self-reported PedsQL scores decreased with increasing child weight. The parent-proxy total PedsQL mean (SD) score for children who were not overweight was 83.1 (12.5); overweight, 80.0 (13.6); and obese, 75.0 (14.5); P < .001. The respective child self-reported total PedsQL mean (SD) scores were 80.5 (12.2), 79.3 (12.8), and 74.0 (14.2); P < .001. At the subscale level, child and parent-proxy reported scores were similar, showing decreases in physical and social functioning for obese children compared with children who were not overweight (all P < .001). Decreases in emotional and school functioning scores by weight category were not significant.

Conclusion: The effects of child overweight and obesity on health-related QOL in this community-based sample were significant but smaller than in a clinical sample using the same measure.

Change in the prevalence of overweight and obesity among young Australian, 1969-1997

BACKGROUND: Effective public policy requires information on the prevalence of overweight and obesity. OBJECTIVE: We determined changes in the population prevalence of overweight and obesity among young Australians (aged 7-15 y) from 1969 to 1985 to 1997. DESIGN: Data from 5 independent population surveys were analyzed: the Australian Youth Fitness Survey, 1969; the Australian Health and Fitness Survey, 1985; the South Australian Schools Fitness and Physical Activity Survey, 1997; the New South Wales Schools Fitness and Physical Activity Survey, 1997; and the Health of Young Victorians Study, 1997. Measured body mass index was used as the index of adiposity, and recently published body mass index cutoff values were used to categorize each subject as nonoverweight, overweight, obese, or either overweight or obese. RESULTS: For 1985-1997, the population prevalence of overweight increased by 60-70%, obesity increased 2-4-fold, and the combined overweight and obesity categories doubled. The findings were consistent across data sets and between the sexes. For 1969-1985, there was no change in the prevalence of overweight or obesity among girls, but among boys the prevalence of overweight increased by 35%, the prevalence of obesity trebled, and the prevalence of overweight and obesity combined increased by 60%. CONCLUSIONS: The data show that in 1985-1997, the prevalence of overweight and obesity combined doubled and that of obesity trebled among young Australians, but the increase over the previous 16 y was far smaller. These results should increase our sense of urgency in identifying and implementing effective responses to this major threat to public health.

Personal, social and environmental determinants of educational inequalities in walking: a multilevel study

Objective: To investigate the contribution of personal, social and environmental factors to mediating socioeconomic (educational) inequalities in women’s leisure-time walking and walking for transport.
Methods: A community sample of 1282 women provided survey data on walking for leisure and transport; educational level; enjoyment of, and self-efficacy for, walking; physical activity barriers and intentions; social support for physical activity; sporting/recreational club membership; dog ownership; and perceived environmental aesthetics and safety. These data were linked with objective environmental data on the density of public open space and walking tracks in the women’s local neighbourhood, coastal proximity and street connectivity.
Results: Multilevel modelling showed that different personal, social and environmental factors were associated with walking for leisure and walking for transport. Variables from all three domains explained (mediated) educational inequalities in leisure-time walking, including neighbourhood walking tracks; coastal proximity; friends’ social support; dog ownership; self-efficacy, enjoyment and intentions. On the other hand, few of the variables examined explained educational variations in walking for transport, exceptions being neighbourhood, coastal proximity, street connectivity and social support from family.
Conclusions: Public health initiatives aimed at promoting, and reducing educational inequalities in, leisure-time walking should incorporate a focus on environmental strategies, such as advocating for neighbourhood walking tracks, as well as personal and social factors. Further investigation is required to better understand the pathways by which education might influence walking for transport.

Changes in body composition as determinants of longitudinal changes in bone mineral measures in 8 to 26 year old female twins

Between 1990 and 1998, we conducted a longitudinal study of 286 female twins aged 8 to 25 years at baseline (60 monozygotic (MZ) pairs, 44 dizygotic (DZ) pairs and 78 unpaired twins), measured on average 2.4 times (range 2–6) with an average of 1.8 years between measurements (range 0.7–6.7 years). Areal bone mineral density (ABMD) at the lumbar spine, total hip and femoral neck, total body bone mineral content (BMC), total body soft tissue composition (lean mass and fat mass) were measured by dual-energy X-ray absorptiometry, and height and menarchial status were also recorded. Median annual changes in height were negligible at 4 years post-menarche. During the “linear growth” period up to 4 years post-menarche, ABMD at the lumbar spine, total hip and femoral neck increased with annual change in lean mass by 1.7 (S.E. 0.1), 1.4 (0.1) and 1.0 (0.1) percent per kilogram per year, respectively (all p<0.001), independently of changes in fat mass or height. During the “post-linear growth” period, ABMD at the total hip and femoral neck increased with annual change in fat mass by 0.3 (0.1) and 0.5 (0.1) percent per kilogram per year (all p<0.01), independent of change in lean mass. Annual changes in total body BMC were associated with annual changes in lean mass (1.9 (0.2) percent per kilogram), in fat mass (1.3 (0.2) percent per kilogram) and in height (0.7) (0.2) percent per centimeter) during linear growth, and in fat mass (1.0 (0.1)) and lean mass (0.6 (0.1)) percent per kilogram post-linear growth (all p<0.001). We conclude that changes in bone mineral measures are strongly associated with changes in lean mass during linear growth, while post-linear growth, changes in fat mass are the predominant, although weaker, predictor. These findings suggest that the strong cross-sectional association between bone mineral measures and lean mass is established during growth and development, and that fat mass emerges as a more powerful determinant of bone change in healthy adult females.

The DALY, context and the determinants of the severity of disease: an exploratory comparison of paraplegia in Australia and Cameroon

This paper summarises the findings of an empirical investigation of some of the technical and social assumptions on which the disability adjusted life year (DALY) is based. The objectives of the study were to examine the notion that the burden of disease is broadly similar without regard to country, environment, gender or socio-economic status and to develop detailed descriptions of the experiences of the burden of disease as they related to these contextual factors. The study was a multi-factorial exploratory study employing qualitative and quantitative techniques to obtain data on the effects of country (development), environment (urban versus rural), gender and socio-economic status on people with paraplegia. The data provided an extensive and detailed compilation of context rich descriptions of living with paraplegia. Striking features of the data were the differences between countries with respect to the impact of the health conditions on functioning and highlight a context in which paraplegia of like clinical severity can be fatal in one environment and not in another. While there has been some focus on the control of social determinants of disease, there has been little work on the social determinants of the severity of disease. The underlying assumptions of the DALY, which ignore context in the assessment of the burden of disease, risk exacerbating inequalities by undervaluing the burden of disease in less-developed countries. There is a need to continue to subject the development of indicators to rigorous debate to determine a balance between the assumption of a global “average social milieu” and the treatment of each individual as belonging to their own context in the assessment of population health in order for indicators to be meaningful cross-culturally.