Ten per cent of the world’s school-aged children are estimated to be carrying excess body fat (Fig. 1), with an increased risk for developing chronic disease. Of these overweight children, a quarter are obese, with a significant likelihood of some having multiple risk factors for type 2 diabetes, heart disease and a variety of other co-morbidities before or during early adulthood. The prevalence of overweight is dramatically higher in economically developed regions, but is rising significantly in most parts of the world. In many countries the problem of childhood obesity is worsening at a dramatic rate. Surveys during the 1990s show that in Brazil and the USA, an additional 0.5% of the entire child population became overweight each year. In Canada, Australia and parts of Europe the rates were higher, with an additional 1% of all children becoming overweight each year. The burden upon the health services cannot yet be estimated. Although childhood obesity brings a number of additional problems in its train – hyperinsulinaemia, poor glucose tolerance and a raised risk of type 2 diabetes, hypertension, sleep apnoea, social exclusion and depression – the greatest health problems will be seen in the next generation of adults as the present childhood obesity epidemic passes through to adulthood. Greatly increased rates of heart disease, diabetes, certain cancers, gall bladder disease, osteoarthritis, endocrine disorders and other obesityrelated conditions will be found in young adult populations, and their need for medical treatment may last for their remaining life-times. The costs to the health services, the losses to society and the burdens carried by the individuals involved will be great. The present report has been written to focus attention on the issue and to urge policy-makers to consider taking action before it is too late. Specifically, the report:

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1467-789X.2004.00133.x

Obesity in children and young people: a crisis in public health.

Childhood obesity affects both the physical and psychosocial health of children and may put them at risk of ill health as adults. More information is needed about the best way to treat obesity in children and adolescents. In this review, 64 studies were examined including 54 studies on lifestyle treatments (with a focus on diet, physical activity or behaviour change) and 10 studies on drug treatment to help overweight and obese children and their families with weight control. No surgical treatment studies were suitable to include in this review. This review showed that lifestyle programs can reduce the level of overweight in child and adolescent obesity 6 and 12 months after the beginning of the program. In moderate to severely obese adolescents, a reduction in overweight was found when either the drug orlistat, or the drug sibutramine were given in addition to a lifestyle program, although a range of adverse effects was also noted. Information on the long-term outcome of obesity treatment in children and adolescents was limited and needs to be examined in some high quality studies.

/pdf/interventions-for-treating-obesity-in-children-ha34h26e60.pdf

Interventions for treating obesity in children

Summary The prevalence of overweight among children has doubled within the past two decades. Increases in the rate of childhood overweight are of particular concern due to the negative health and psychological effects noted among overweight children. As shown by previous research, the development of childhood overweight involves a complex set of factors from multiple contexts that interact with each other to place a child at risk of overweight. This multifaceted system can be conceptualized using Ecological Systems Theory (EST). EST highlights the importance of considering the context(s), or ecological niche, in which a person is located in order to understand the emergence of a particular characteristic. In the case of a child, the ecological niche includes the family and the school, which are in turn embedded in larger social contexts including the community and society at large. In this review, EST is used as a framework with which to summarize research assessing predictors of childhood overweight. Specifically, child characteristics that place children at risk of the development of overweight (including dietary intake, physical activity, and sedentary behaviour) will be reviewed while taking into consideration the influence of the familial environment, the school environment, and the community and larger social environments. It is concluded that future research needs to adopt a broader contextual approach in order to understand and intervene against the processes leading to the development of overweight among children and that the use of theories or paradigms such as EST will facilitate developing and testing models of causal processes.

/pdf/childhood-overweight-a-contextual-model-and-recommendations-94icr885ss.pdf

Childhood overweight: a contextual model and recommendations for future research

OBJECTIVE
To identify factors in childhood which might influence the development of obesity in adulthood.


BACKGROUND
The prevalence of obesity is increasing in the UK and other developed countries, in adults and children. The adverse health consequences of adult obesity are well documented, but are less certain for childhood obesity. An association between fatness in adolescence and undesirable socio-economic consequences, such as lower educational attainment and income, has been observed, particularly for women. Childhood factors implicated in the development of adult obesity therefore have far-reaching implications for costs to the health-services and economy.


SEARCH STRATEGY
In order to identify relevant studies, electronic databases--Medline, Embase, CAB abstracts, Psyclit and Sport Discus-were searched from the start date of the database to Spring 1998. The general search structure for electronic databases was (childhood or synonyms) AND (fatness or synonyms) AND (longitudinal or synonyms). Further studies were identified by citations in retrieved papers and by consultation with experts.


INCLUSION CRITERIA
Longitudinal observational studies of healthy children which included measurement of a risk factor in childhood (<18 y), and outcome measure at least 1 y later. Any measure of fatness, leanness or change in fatness or leanness was accepted. Measures of fat distribution were not included. Only studies with participants from an industrialized country were considered, and those concerning minority or special groups, e.g. Pima Indians or children born preterm, were excluded.


FINDINGS
Risk factors for obesity included parental fatness, social factors, birth weight, timing or rate of maturation, physical activity, dietary factors and other behavioural or psychological factors. Offspring of obese parent(s) were consistently seen to be at increased risk of fatness, although few studies have looked at this relationship over longer periods of childhood and into adulthood. The relative contributions of genes and inherited lifestyle factors to the parent-child fatness association remain largely unknown. No clear relationship is reported between socio-economic status (SES) in early life and childhood fatness. However, a strong consistent relationship is observed between low SES in early life and increased fatness in adulthood. Studies investigating SES were generally large but very few considered confounding by parental fatness. Women who change social class (social mobility) show the prevalence of obesity of the class they join, an association which is not present in men. The influence of other social factors such as family size, number of parents at home and childcare have been little researched. There is good evidence from large and reasonably long-term studies for an apparently clear relationship for increased fatness with higher birth weight, but in studies which attempted to address potential confounding by gestational age, parental fatness, or social group, the relationship was less consistent. The relationship between earlier maturation and greater subsequent fatness was investigated in predominantly smaller, but also a few large studies. Again, this relationship appeared to be consistent, but in general, the studies had not investigated whether there was confounding by other factors, including parental fatness, SES, earlier fatness in childhood, or dietary or activity behaviours. Studies investigating the role of diet or activity were generally small, and included diverse methods of risk factor measurement. There was almost no evidence for an influence of activity in infancy on later fatness, and inconsistent but suggestive evidence for a protective effect of activity in childhood on later fatness. No clear evidence for an effect of infant feeding on later fatness emerged, but follow-up to adulthood was rare, with only one study measuring fatness after 7y. Studies investigating diet in childhood were limited and inconc

Childhood predictors of adult obesity: a systematic review.

Obesogenic environments are thought to underlie the increased obesity prevalence observed in youth during the past decades. Understanding the environmental factors that are associated with physical activity (PA) in youth is needed to better inform the development of effective intervention strategies attempting to halt the obesity epidemic. We conducted a systematic semi-quantitative review of 150 studies on environmental correlates of youth PA published in the past 25 years. The ANalysis Grid for Environments Linked to Obesity (ANGELO) framework was used to classify the environmental correlates studied. Most studies retrieved used cross-sectional designs and subjective measures of environmental factors and PA. Variables of the home and school environments were especially associated with children's PA. Most consistent positive correlates of PA were father's PA, time spent outdoors and school PA-related policies (in children), and support from significant others, mother's education level, family income, and non-vocational school attendance (in adolescents). Low crime incidence (in adolescents) was characteristic of the neighbourhood environment associated with higher PA. Convincing evidence of an important role for many other environmental factors was, however, not found. Further research should aim at longitudinal and intervention studies, and use more objective measures of PA and its potential (environmental) determinants.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1467-789X.2006.00264.x

Environmental correlates of physical activity in youth - a review and update.

OBJECTIVE: To study differences in physical activity between normal-weight and obese children, as well as parent–child associations of obesity and physical activity. DESIGN: Cross-sectional study. SUBJECTS: 129 obese children (67 girls and 62 boys), 142 normal-weight controls (81 boys and 61 girls), and mothers (n=245) and fathers (n=222) of the children. METHODS: Physical activity was assessed by a 3-day physical activity record (children and parents), by a questionnaire (children), and by one question on habitual physical activity (parents). The data were analysed by stepwise linear and logistic regressions. Obesity was assessed from relative weight (children) and BMI (parents). RESULTS: Parent inactivity was a strong and positive predictor of child inactivity (β-coefficients 0.25 and 0.16, P<0.001, for mother and father inactivity, respectively). Scores of parent activity were somewhat weaker predictors of child vigorous activity hours and total physical activity level (β-coefficients 0.13–0.25, P=0.003–0.08). Child obesity was negatively associated with child habitual physical activity (odds ratio 0.88, P<0.001). In addition, parent obesity (body mass index ≥30 kg/m2) was another strong predictor of child obesity (odds ratio 2.38–3.50, P<0.002). CONCLUSIONS: The present study underscores the parents’ role in childhood activity patterns and obesity. A novel finding was that the parent–child relationship of inactivity appeared to be stronger than that of vigorous activity. Hence, parents who want to reduce their children’s inactivity may have to pay attention to their own lifestyle.

Parent-child relationship of physical activity patterns and obesity.

The aim of the study was to compare the efficacy of group treatment stressing a health-promoting lifestyle with routine counseling in the treatment of childhood obesity. Seventy obese children (weight for height 115–182%) aged 7–9 years were randomized either to routine counseling (two appointments for children) or to family-based group treatment (15 separate sessions for parents and children). These sessions included nutrition education, physical activity education and behavioral therapy. Children's weights and heights were measured at baseline, after the 6-month intervention and after the 6-month follow-up. The change of weight for height based on Finnish growth charts was used as the primary, and changes in body mass index (BMI) and BMI standard deviation scores (BMI-SDS) as secondary outcome measures. Children attending the group treatment lost more weight for height (6.8%) than children receiving routine counseling (1.8%) (P=0.001). The difference was significant when the data were analyzed in four groups by the cut-off limits of 0, −5 and −10% for the change in weight for height. The respective decreases in BMI were 0.8 vs 0.0 (P=0.003) and in BMI-SDS 0.3 vs 0.2 (P=0.022). The results remained similar in adjusted analyses. Both group and routine programs were feasible with a high, 87–99%, participation rate in sessions and appointments and very low, 3% or less, attrition rate from the programs. Six months after the intervention, beneficial effects were partly lost, but for changes in weight for height and BMI, the differences between the two treatment programs still were significant, and for BMI-SDS, there was a trend. Family-based group treatment that stresses a health-promoting lifestyle and is given separately for parents and children, offers an effective mode of therapy to treat obese school-aged children.

Clinical efficacy of group-based treatment for childhood obesity compared with routinely given individual counseling.

Previous studies have shown strong parental influences on adolescent overweight. However, longitudinal data is scarce on gender-specific effects of parental body mass index (BMI) on offspring overweight. The objective of this study was to examine the associations of parental pre-pregnancy BMI, weight change, BMI and BMI class transition 16 years after pregnancy with the BMI of their 16-year-old children. The study population was derived from the general population-based Northern Finland Birth Cohort 1986. A total of 4788 child–mother–father trios (2325 boys, 2463 girls) were analysed. Weight and height of the adolescents were measured and overweight and obesity defined according to the International Obesity Task Force. For the parents, self-reported data were obtained and overweight and obesity defined according to the World Health Organization. Associations of parental BMI status and weight change with offspring BMI were assessed using binary logistic regression analyses stratified by gender and adjusted for parental age and education. Children whose both parents were overweight or obese both before pregnancy and after 16-year follow-up had a strikingly high risk of overweight at age 16 years (boys odds ratio (OR) 5.66 95% confidence interval (CI) 3.12, 10.27; girls OR 14.84 95% CI 7.41, 29.73). Parental pre-pregnancy obesity strongly predicted offspring overweight (mother–son OR 4.36 95% CI 2.50, 7.59; mother–daughter OR 3.95 95% CI 2.34, 6.68; father–son OR 3.17 95% CI 1.70, 5.92; father–daughter OR 5.58 95% CI 3.09, 10.07). Parental overweight conveys a major risk for overweight in children for which both parents’ long-term overweight (BMI ⩾25 kg m−2 before pregnancy and after 16-year follow-up) was the strongest single predictor. Preventing intergenerational transmission of obesity by helping parents to maintain a healthy weight is an essential target for public health.

Intergenerational transmission of overweight among Finnish adolescents and their parents: a 16-year follow-up study

Long-term effects of weight reduction on serum lipids and plasma insulin in obese children.

The characteristics of successful and unsuccessful weight losers were studied in 48 obese children (relative weight > 120%) aged 6-15 years who were treated for 1 year and observed for another. Successful weight loss was defined as a decrease in relative weight of > or = 0.8 in the standard deviation score (SDS) at the end of the study. Thirty-two children were treated intensively, 16 with individual counselling and 16 in group therapy, while the remaining 16 children were treated conventionally in a school health care setting. Three children dropped out of the study. In 2 years, the relative body weight decreased by 1.7 SDS in those who were successful weight losers (n = 21, 47%), but remained unchanged in those who had been unsuccessful (n = 24). At baseline there were no differences between the two groups. At 1 year, the successful weight losers had lower body weight (P < 0.05), less lean body mass (0.05) and lower fasting concentrations of circulating insulin (P < 0.01) than the unsuccessful children did. A decrease in mothers' body mass index (BMI) and in documented energy intake over the first year as well as energy intake at 1 year were significant predictors of success at 2 years. The combination of these three predictors resulted in correct classification of about 3/4 of the cases as successful or unsuccessful weight losers. It appears, however, difficult to develop a clinically useful model for predicting the treatment outcome in obese children.

Outi Nuutinen

Papers

Parent-child relationship of physical activity patterns and obesity.

Clinical efficacy of group-based treatment for childhood obesity compared with routinely given individual counseling.

Intergenerational transmission of overweight among Finnish adolescents and their parents: a 16-year follow-up study

Long-term effects of weight reduction on serum lipids and plasma insulin in obese children.

Predictors of weight reduction in obese children.