The prevention of overweight and obesity in children and adolescents: a review of interventions and programmes

Overweight and obesity are serious, large-scale, global, public health concerns requiring population-based childhood overweight and obesity prevention. The overall objective of this review is to identify aspects of successful childhood overweight prevention programmes. This objective will be met by assessing existing interventions quantitatively as well as qualitatively, identifying efficacy, effectiveness and implementation, and evaluating potential adverse effects of previous studies. This review was limited to school-based studies with a quantitative evaluation using anthropometric outcomes and that intervene on diet or activity-related behaviours. Quantitative and qualitative approaches are used to identify factors related to successful interventions as well as adverse consequences. Sixty-eight per cent of the interventions, or 17 of the 25, were 'effective' based on a statistically significant reduction in body mass index (BMI) or skin-folds for the intervention group. Four interventions were effective by BMI as well as skin-fold measures. Of these, two targeted reductions in television viewing. The remaining two studies targeted direct physical activity intervention through the physical education programme combined with nutrition education. Of the interventions reported here, one was effective in reducing childhood overweight but was also associated with an increase in underweight prevalence. Few other studies reported outcomes for underweight. The majority of overweight/obesity prevention programmes included in this review were effective. Physical education in schools and reducing television viewing are two examples of interventions that have been successful. Because few studies report on underweight prevalence, this review recommends giving more attention to preventing adverse outcomes by reporting the intervention impact on the frequency distribution for both BMI and adiposity measures.     

Systematic review of school-based interventions that focus on changing dietary intake and physical activity levels to prevent childhood obesity: an update to the obesity guidance produced by the National Institute for Health and Clinical Excellence

To determine the effectiveness of school-based interventions that focus on changing dietary intake and physical activity levels to prevent childhood obesity. MEDLINE and EMBASE were searched (January 2006 to September 2007) for controlled trials of school-based lifestyle interventions, minimum duration of 12 weeks, reporting weight outcome. Thirty-eight studies were included; 15 new studies and 23 studies included within the National Institute for Health and Clinical Excellence obesity guidance. One of three diet studies, five of 15 physical activity studies and nine of 20 combined diet and physical activity studies demonstrated significant and positive differences between intervention and control for body mass index. There is insufficient evidence to assess the effectiveness of dietary interventions or diet vs. physical activity interventions. School-based physical activity interventions may help children maintain a healthy weight but the results are inconsistent and short-term. Physical activity interventions may be more successful in younger children and in girls. Studies were heterogeneous, making it difficult to generalize about what interventions are effective. The findings are inconsistent, but overall suggest that combined diet and physical activity school-based interventions may help prevent children becoming overweight in the long term. Physical activity interventions, particularly in girls in primary schools, may help to prevent these children from becoming overweight in the short term.     

The influence of maternal body mass index,maternal diabetes mellitus,and maternal smoking during pregnancy on the risk of childhood‐onset type 1 diabetes mellitus in the offspring: Systematic review and meta‐analysis of observational studies

There is emerging evidence that events occurring before and shortly after birth may be important in determining the risk of childhood‐onset type 1 diabetes mellitus (T1DM). We aimed to summarize and synthesize the associations between maternal body mass index (BMI), maternal diabetes mellitus (DM), and maternal smoking during pregnancy and the risk of childhood‐onset T1DM in the offspring by performing a systematic review and meta‐analysis of observational studies. A random effects model was used to generate the summary risk estimates. The PubMed and Web of Science databases were searched to identify relevant observational studies. Twenty one observational studies were included in the present meta‐analysis. Compared with offspring of mothers with normal weight, offspring of women with overweight or obesity were at an increased risk of developing childhood‐onset T1DM (overweight: relative risk [RR] 1.09, 95% confidence interval [CI], 1.03‐1.15; obesity: RR 1.25, 95% CI, 1.16‐1.34; per 5 kg m^?2 increase in BMI: RR 1.10, 95% CI, 1.06‐1.13). No association was found for maternal underweight (RR 0.92, 95% CI, 0.75‐1.13). Maternal DM was associated with an increased risk of childhood‐onset T1DM (RR 3.26, 95% CI, 2.84‐3.74). Regarding the type of maternal DM, the greatest risk of T1DM in the offspring appeared to be conferred by maternal T1DM (RR 4.46, 95% CI, 2.89‐6.89), followed by maternal gestational diabetes mellitus (RR 1.66, 95% CI, 1.16‐2.36), and lastly by maternal type 2 diabetes mellitus (RR 1.11, 95% CI, 0.69‐1.80). Additional analysis of studies comparing maternal versus paternal T1DM within the same population revealed that offspring of fathers with T1DM had a 1.5 times higher risk of developing childhood‐onset T1DM than offspring of mothers with T1DM (RR 9.58, 95% CI, 6.33‐14.48 vs. RR 6.24, 95% CI, 5.52‐7.07). Furthermore, a reduced risk of childhood‐onset T1DM was observed in infants born to mothers who smoked during pregnancy compared with infants born to mothers who did not smoke during pregnancy (RR 0.79, 95% CI, 0.71‐0.87). In summary, our findings add further evidence that early‐life events or environmental factors may play a role in modulating infants' risk of developing T1DM later in life.     

The effects of school‐based lifestyle interventions on body mass index and blood pressure: a multivariate multilevel meta‐analysis of randomized controlled trials

Primary prevention of childhood obesity and related hypertension is warrant given that both risk factors are intertwined and track into adulthood. This systematic review and meta‐analysis assess the impact of school‐based lifestyle interventions on children's body mass index (BMI) and blood pressure. We searched databases and prior reviews. Eligibility criteria were the following: randomized controlled trial design, evaluation of a school‐based intervention, targeting children aged 4–12 years, reporting on BMI and/or related cardiovascular risk factors, reporting data on at least one follow‐up moment. The effects on BMI, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were evaluated by means of univariate and multivariate three‐level random effects models. A total of 85 RCTs (91 papers) were included in the meta‐analyses. In univariate models, the pooled effects were ?0.072 (95%CI: ?0.106; ?0.038) for BMI, ?0.183 (95%CI: ?0.288; ?0.078) for SBP and ?0.071 (95%CI: ?0.185; 0.044) for DBP. In multivariate analyses, the pooled effects of interventions were ?0.054 (95%CI: ?0.131; 0.022) for BMI, ?0.182 (95%CI: ?0.266; ?0.098) for SBP and ?0.144 (95%CI: ?0.230; ?0.057) for DBP. Parental involvement accentuated the beneficial effects of interventions. School‐based lifestyle prevention interventions result in beneficial changes in children's BMI and blood pressure, and the effects on the latter may be stronger than and accrue independently from those in the former.     

Effectiveness of school‐based interventions to prevent obesity among children aged 4 to 12 years old in middle‐income countries: A systematic review and meta‐analysis

Economic and accompanying nutrition transition in middle‐income countries is resulting in rapidly increasing childhood obesity prevalence, exceeding acceleration rates in the West. Previous school‐based obesity prevention reviews have mainly included studies from high‐income countries. This review aimed to summarize the evidence from randomized controlled trials evaluating the effectiveness of school‐based interventions in preventing childhood obesity in middle‐income countries. Six electronic databases were searched: MEDLINE, EMBASE, CINAHL Plus, LILACS, IBECS and WPRIM. Eligibility criteria included middle‐income country setting, randomized/cluster‐randomized controlled trials, children aged 4–12 years and school‐based interventions targeting dietary intake and/or physical activity. Twenty‐one cluster‐randomized controlled trials, conducted in Asia (n = 10), South America (n = 4), North America (n = 4) and the Middle East (n = 3), were included. Fifteen studies reported a significant intervention effect on at least one adiposity‐related outcome. Characteristics of effective interventions included combined diet and PA interventions, school teacher‐delivery, duration of >8 months, parental involvement, education sessions and school food modifications. The risk of bias in these trials was mixed. The pooled estimate of the odds ratio for obesity in intervention versus control schools (nine studies) was 0.77; 95% CI, 0.63 to 0.94; p = 0.009. In conclusion, there is some evidence to support school‐based interventions in preventing childhood obesity in middle‐income countries.     

School‐based interventions promoting both physical activity and healthy eating in Europe: a systematic review within the HOPE project

It is the purpose of this study to systematically review the evidence of school‐based interventions targeting dietary and physical activity behaviour in primary (6–12 years old) and secondary school (12–18 years old) children in Europe. Eleven studies (reported in 27 articles) met the inclusion criteria, six in primary school and five in secondary school children. Interventions were evaluated in terms of behavioural determinants, behaviour (diet and physical activity) and weight‐related outcomes (body mass index [BMI] or other indicators of obesity). The results suggest that combining educational and environmental components that focus on both sides of the energy balance give better and more relevant effects. Furthermore, computer‐tailored personalized education in the classroom showed better results than a generic classroom curriculum. Environmental interventions might include organized physical activities during breaks, or before and after school; improved availability of physical activity opportunities in and around the school environment; increased physical education lesson time; improved availability or accessibility of healthy food options; and restricted availability and accessibility of unhealthy food options. More high‐quality studies are needed to assess obesity‐related interventions in Europe.     

The effectiveness of sedentary behaviour interventions for reducing body mass index in children and adolescents: systematic review and meta‐analysis

Intervention studies have been undertaken to reduce sedentary behaviour (SB) and thereby potentially ameliorate unhealthy weight gain in children and adolescents. We synthesised evidence and quantified the effects of SB interventions (single or multiple components) on body mass index (BMI) or BMI z‐score in this population. Publications up to March 2015 were located through electronic searches. Inclusion criteria were interventions targeting SB in children that had a control group and objective measures of weight and height. Mean change in BMI or BMI z‐score from baseline to post‐intervention were quantified for intervention and control groups and meta‐analyzed using a random effects model. The pooled mean reduction in BMI and BMI z‐score was significant but very small (standardized mean difference = ?0.060, 95% confidence interval: ?0.098 to ?0.022). However, the pooled estimate was substantially greater for an overweight or obese population (standardized mean difference = ?0.255, 95% confidence interval: ?0.400 to ?0.109). Multicomponent interventions (SB and other behaviours) delivered to children from 5 to 12 years old in a non‐educational setting appear to favour BMI reduction. In summary, SB interventions are associated with very small improvement in BMI in mixed‐weight populations. However, SB interventions should be part of multicomponent interventions for treating obese children. © 2016 World Obesity     

Longitudinal impact of sleep on overweight and obesity in children and adolescents: a systematic review and bias‐adjusted meta‐analysis

Short sleep duration is considered a potential risk for overweight/obesity in childhood and adolescence. However, most of the evidence on this topic is obtained from cross‐sectional studies; therefore, the nature and extent of the longitudinal associations are unclear. This study explores the prospective association between short sleep and overweight/obesity in young subjects. The MEDLINE, EMBASE, Pubmed, and CINAHL databases were searched for English‐language articles, published until May 2014, reporting longitudinal association between sleep and body mass index (BMI) in children and adolescents. Recommendations of the Sleep Health Foundation were used to standardize reference sleep duration. Sleep category, with sleep duration less than the reference sleep, was considered as the short sleep category. Meta‐analysis was conducted to explore the association between short sleep and overweight/obesity. A review of 22 longitudinal studies, with subjects from diverse backgrounds, suggested an inverse association between sleep duration and BMI. Meta‐analysis of 11 longitudinal studies, comprising 24,821 participants, revealed that subjects sleeping for short duration had twice the risk of being overweight/obese, compared with subjects sleeping for long duration (odds ratio 2.15; 95% confidence interval: 1.64–2.81). This study provides evidence that short sleep duration in young subjects is significantly associated with future overweight/obesity.     

青年和中年时期体重状态变化及最大体重减重程度与其中老年时期2型糖尿病的关系

目的探讨青年及中年时期人群,发生超重和肥胖后的体重状态变化以及最大体重减重程度与其中老年期发生T2DM的关系。方法基于中国糖尿病和代谢紊乱研究库,选取19878名年龄≥40岁的中老年人群,采用多因素Logistic回归分析既往超重及肥胖[最大BMI(BMIMax)≥24.0 kg/m^2]发生在青年及中年时期人群的体重状态变化及最大体重减重程度与T2DM患病风险的关系。结果与正常体重组(BMIMax及BMI 18.5~23.9 kg/m^2)相比,青年时期持续超重组(BMIMax及BMI≥24.0 kg/m^2)、青年时期既往超重组(BMIMax≥24.0 kg/m^2,BMI 18.5~23.9 kg/m^2)、中年时期持续超重组(BMIMax及BMI≥24.0 kg/m^2)、中年时期既往超重组(BMIMax≥24.0 kg/m^2,BMI 18.5~23.9 kg/m^2)的T2DM患病风险均不同程度增加,以青年时期持续超重组最高(OR 2.57,95%CI 2.21~2.99)。超重人群(BMIMax≥24.0 kg/m^2)中,与减重<5%人群相比,减重≥5%人群T2DM患病风险增高,以减重≥15%人群风险最高(OR 3.58,95%CI 3.07~4.17)。结论无论目前体重正常或超重,青年及中年时期人群发生超重及肥胖均增加其中老年时期T2DM患病风险。超重人群最大体重减重≥5%时,中老年T2DM患病风险增加。     

Resolved: there is sufficient scientific evidence that decreasing sugar‐sweetened beverage consumption will reduce the prevalence of obesity and obesity‐related diseases

Sugar‐sweetened beverages (SSBs) are the single largest source of added sugar and the top source of energy intake in the U.S. diet. In this review, we evaluate whether there is sufficient scientific evidence that decreasing SSB consumption will reduce the prevalence of obesity and its related diseases. Because prospective cohort studies address dietary determinants of long‐term weight gain and chronic diseases, whereas randomized clinical trials (RCTs) typically evaluate short‐term effects of specific interventions on weight change, both types of evidence are critical in evaluating causality. Findings from well‐powered prospective cohorts have consistently shown a significant association, established temporality and demonstrated a direct dose–response relationship between SSB consumption and long‐term weight gain and risk of type 2 diabetes (T2D). A recently published meta‐analysis of RCTs commissioned by the World Health Organization found that decreased intake of added sugars significantly reduced body weight (0.80 kg, 95% confidence interval [CI] 0.39–1.21; P < 0.001), whereas increased sugar intake led to a comparable weight increase (0.75 kg, 0.30–1.19; P = 0.001). A parallel meta‐analysis of cohort studies also found that higher intake of SSBs among children was associated with 55% (95% CI 32–82%) higher risk of being overweight or obese compared with those with lower intake. Another meta‐analysis of eight prospective cohort studies found that one to two servings per day of SSB intake was associated with a 26% (95% CI 12–41%) greater risk of developing T2D compared with occasional intake (less than one serving per month). Recently, two large RCTs with a high degree of compliance provided convincing data that reducing consumption of SSBs significantly decreases weight gain and adiposity in children and adolescents. Taken together, the evidence that decreasing SSBs will decrease the risk of obesity and related diseases such as T2D is compelling. Several additional issues warrant further discussion. First, prevention of long‐term weight gain through dietary changes such as limiting consumption of SSBs is more important than short‐term weight loss in reducing the prevalence of obesity in the population. This is due to the fact that once an individual becomes obese, it is difficult to lose weight and keep it off. Second, we should consider the totality of evidence rather than selective pieces of evidence (e.g. from short‐term RCTs only). Finally, while recognizing that the evidence of harm on health against SSBs is strong, we should avoid the trap of waiting for absolute proof before allowing public health action to be taken.     

Effect of childhood obesity prevention programmes on blood lipids: a systematic review and meta‐analysis

We aimed to assess the effects of childhood obesity prevention programmes on blood lipids in high‐income countries. We searched MEDLINE®, Embase, PsychInfo, CINAHL®, clinicaltrials.gov , and the Cochrane Library up to 22 April 2013 for relevant randomized controlled trials, quasi‐experimental studies and natural experiments published in English. Studies were included if they implemented diet and/or physical activity intervention(s) with ≥1 year follow‐up (or ≥6 months for school‐based intervention studies) in 2–18‐year‐olds, and were excluded if they targeted only overweight/obese children, or those with a pre‐existing medical condition. Seventeen studies were finally included. For total cholesterol, the pooled intervention effect was ?0.97 mg dL^?1 [95% confidence interval (CI): ?3.26, 1.32; P = 0.408]; for low‐density lipoprotein cholesterol (LDL‐C), ?6.06 mg dL^?1 (95% CI: ?11.09, ?1.02; P = 0.018); for high‐density lipoprotein cholesterol (HDL‐C), 1.87 mg dL^?1 (95% CI: 0.39, 3.34; P = 0.013); and for triglycerides, ?1.95 mg dL^?1 (95% CI: ?4.94, 1.04; P = 0.202). Most interventions (70%) showed similar significant or no effects on adiposity‐ and lipids outcomes: 15% interventions improved both adiposity‐ and lipids outcomes; 55% had no significant effects on either. Childhood obesity prevention programmes had a significant desirable effect on LDL‐C and HDL‐C. Two‐thirds of interventions showed similar significant or no effects in adiposity‐ and lipids outcomes. Assessing lipids outcomes provide additional useful information on obesity prevention programme benefits.     

Effects of lifestyle interventions and long‐term weight loss on lipid outcomes – a systematic review

Weight and lipids are critical components of the metabolic syndrome, diabetes and cardiovascular disease. Past reviews considering weight loss on lipid profiles have been for ≤1 year follow‐up and/or were for very overweight, obese or morbidly obese participants. This systematic review includes lifestyle interventions for adults (18–65 years), with a mean baseline BMI < 35 kg/m², with weight and lipid differences over 2 years. Between 1990 and 2010, 14 studies were identified. Mean differences for weight and lipids were modest. However, weight loss at 2–3 years follow‐up, produced significant beneficial lipid profile changes. These were similar to previous reviews conducted on heavier target groups and/or over shorter follow‐up periods; cholesterol (1.3% decrease per kg lost) and triglycerides (1.6% fall per kg). Weight loss sustained longer than 3 years was not associated with beneficial lipid changes, suggesting that other lifestyle changes not just weight loss needs maintaining. Evidence linking lifestyle induced sustained weight loss with lipid profile changes in the long‐term for this group is limited. Probable within‐group differences (treatment vs prevention), would make further group separation prudent. Individual patient data analysis would facilitate this, uncover baseline, medication and confounding effects, and may identify successful program components enabling more effective obesity prevention and treatment strategies.     

2型糖尿病发病的炎症机制

2型糖尿病（T2DM）胰岛素抵抗与胰岛B细胞功能异常的机制包括氧化应激、内质网应激、胰岛淀粉样变性、肌肉与肝脏及胰腺部位异位脂肪沉积、脂毒性以及糖毒性等。上述机制均可因营养过剩而激活,且均可视为某种炎症反应,或与炎症相关。本文就免疫系统参与T2DM致病的有关机制研究以及T2DM抗炎治疗的临床试验做一简要回顾。     

The risk of overweight and obesity in children with autism spectrum disorders: A systematic review and meta‐analysis

Multiple studies have suggested that autism spectrum disorders seem to increase the risk of overweight and obesity. We examined the pooled prevalence and relative risk of developing overweight or obesity among children with autism spectrum disorders in a systematic review and meta‐analysis. We searched PubMed, Scopus, ProQuest, and Web of Science databases and subsequently screened the records to identify studies that reported prevalence of overweight and/or obesity in children with ASD and matched groups of neurotypical children. DerSimonian‐Laird random‐effects meta‐analyses were performed to examine pooled prevalence and relative risk of obesity in children with autism spectrum disorders using the “meta” package in R software. Among children with autism spectrum disorders, the prevalence of obesity was 22.2%. Children with ASD had a 41.1% greater risk (P = .018) of development of obesity. Non‐Caucasian race, increasing age, female sex, and living in the United States emerged as positive moderators of the association between autism spectrum disorders and prevalence of overweight or obesity. Autism spectrum disorders seem to increase the risk of childhood obesity. Increased awareness of this association may allow the implementation of early interventions to reduce obesity and prevent potential deterioration of quality‐of‐life in this population.     

Sugar-Sweetened Beverage,Obesity, and Type 2 Diabetes in Children and Adolescents: Policies,Taxation, and Programs

Purpose of Review

Obesity has grown at an alarming rate in children and adolescents. Concurrently, consumption on sugar-sweetened beverages (SSBs) also rose significantly. This review provides an overview of obesity and type 2 diabetes mellitus (T2DM) related to SSBs and current policies restricting SSBs in schools, school-based interventions, and taxation on reducing SSB intake and obesity. We also discuss challenges of and future steps for these initiatives.

Recent Findings

Clinical and epidemiological studies suggest a strong association between SSB intake and obesity and T2DM. School food policies have been initiated at federal, state, and local levels. School-based interventions have shown positive effects on SSB intake and obesity reduction. Taxation on SSBs is promising in combating obesity and in generating revenue. Challenges towards compliance and implementation of the policies and programs exist.

Summary

The relationship between SSB and obesity and T2DM is a complex problem which requires comprehensive solutions. Continued efforts in restricting SSBs in schools are needed. Intervention programs should be tailored to age, gender, language, and culture and involve participation from families and local communities. Taxation can reduce SSB consumption by direct economic incentive, earmarking revenues to support healthy foods, and sending negative message. However, a higher tax rate may be necessary to have a measurable effect on weight.

     

Physical activity interventions in early life aimed at reducing later risk of obesity and related non‐communicable diseases: A rapid review of systematic reviews

To identify useful components of interventions aimed at prevention of childhood obesity and related non‐communicable diseases (NCDs), which included physical activity and which targeted any or all of four life‐course stages: peri‐conception; pregnancy; infancy and toddlerhood (0 to 23 months); and early childhood (24 to 59 months). In May 2016, WHO Geneva searched the Cochrane Library and PubMed for systematic reviews of interventions including physical activity to prevent childhood obesity or risk factors for obesity‐related NCDs. Using a narrative synthesis, the efficacy of randomized controlled trials (RCTs) to alter energy balance outcomes (measures of weight status or body fatness) was characterized by life‐course stage, study characteristics, intervention functions (as defined in the behaviour change wheel), and level of the socio‐ecological model (SEM) targeted. The quality of included systematic reviews was assessed. We retrieved 82 reviews from the World Health Organization (WHO) search, of which 23 were eligible for the present synthesis. The number of eligible studies by life‐course stage was: 0 (peri‐conception); 0 (pregnancy); 8 (infancy and toddlerhood, age 0 to 23 months; seven RCTs; age); and 37 (early childhood, age 24 to 59 months; 30 RCTs;). Thus, there was a lack of evidence for physical activity interventions during peri‐conception and pregnancy. Almost all relevant studies in the 0‐ to 23‐ and 24‐ to 59‐month life‐course stages were multicomponent interventions (ie, targeted physical activity, dietary, and/or sedentary behaviours). Interventions with evidence of efficacy tended to target multiple levels of the SEM, with emphasis on parents, and extend over long periods. Effective intervention elements for early life obesity prevention included classes on parenting skills, alteration of the kindergarten playground, and financial incentives. Evidence from low‐ and middle‐income countries was scarce, and evidence for intervention effect on obesity‐related NCDs was missing. Future physical activity interventions in toddlerhood and early childhood aimed at prevention of obesity should adopt the characteristics typical of effective interventions identified by the present synthesis. There is an urgent need for more evidence on physical activity interventions set in low‐ and middle‐income countries and which target the peri‐conception and pregnancy periods.     

Environmental components of childhood obesity prevention interventions: an overview of systematic reviews

Childhood obesity has a complex multi‐factorial aetiology grounded in environmental and individual level factors that affect behaviour and outcomes. An ecological, systems‐based approach to addressing childhood obesity is increasingly being advocated. The primary aim of this review is to summarize the evidence reported in systematic reviews on the effectiveness of population‐level childhood obesity prevention interventions that have an environmental component. We conducted a systematic review of reviews published since 1995, employing a standardized search strategy in nine databases. Inclusion criteria required that reviews be systematic and evaluated at least one population‐level, environmental intervention in any setting aimed at preventing or reducing obesity in children (5–18 years). Sixty‐three reviews were included, ten of which were of high quality. Results show modest impact of a broad range of environmental strategies on anthropometric outcomes. Systematic reviews vary in methodological quality, and not all relevant primary studies may be included in each review. To ensure relevance of our findings to practice, we also report on relevant underlying primary studies, providing policy‐relevant recommendations based on the evidence reviewed. Greater standardization of review methods and reporting structures will benefit policymakers and public health professionals seeking informed decision‐making.     

What childhood obesity prevention programmes work? A systematic review and meta‐analysis

Previous reviews of childhood obesity prevention have focused largely on schools and findings have been inconsistent. Funded by the US Agency for Healthcare Research and Quality (AHRQ) and the National Institutes of Health, we systematically evaluated the effectiveness of childhood obesity prevention programmes conducted in high‐income countries and implemented in various settings. We searched MEDLINE®, Embase, PsycINFO, CINAHL®, ClinicalTrials.gov and the Cochrane Library from inception through 22 April 2013 for relevant studies, including randomized controlled trials, quasi‐experimental studies and natural experiments, targeting diet, physical activity or both, and conducted in children aged 2–18 in high‐income countries. Two reviewers independently abstracted the data. The strength of evidence (SOE) supporting interventions was graded for each study setting (e.g. home, school). Meta‐analyses were performed on studies judged sufficiently similar and appropriate to pool using random effect models. This paper reported our findings on various adiposity‐related outcomes. We identified 147 articles (139 intervention studies) of which 115 studies were primarily school based, although other settings could have been involved. Most were conducted in the United States and within the past decade. SOE was high for physical activity‐only interventions delivered in schools with home involvement or combined diet–physical activity interventions delivered in schools with both home and community components. SOE was moderate for school‐based interventions targeting either diet or physical activity, combined interventions delivered in schools with home or community components or combined interventions delivered in the community with a school component. SOE was low for combined interventions in childcare or home settings. Evidence was insufficient for other interventions. In conclusion, at least moderately strong evidence supports the effectiveness of school‐based interventions for preventing childhood obesity. More research is needed to evaluate programmes in other settings or of other design types, especially environmental, policy and consumer health informatics‐oriented interventions.     

Association between body mass index and core components of metabolic syndrome in 1486 patients with type 1 diabetes mellitus in Japan (JDDM 13)

There is no recent study on the prevalence of overweight and obesity in patients with type 1 diabetes mellitus (T1DM) in Japan. Being overweight has a significant effect on the metabolic condition and glycemic control of such patients. In the present cross-sectional study, we investigated the effects of body mass index (BMI) on lipid profile, blood pressure, and glycemic control in patients with T1DM. In total, 1486 patients with T1DM (including 401 patients with early onset T1DM who were <20 years of age at diagnosis) were included. Patients were divided into four groups according to their BMI, and glycosylated hemoglobin (HbA1c), daily insulin dose per kg body weight, lipid profile, and blood pressure were compared between groups. We found that 15.7% of all patients were overweight (BMI >or= 25.0 kg/m(2)) and 2.0% were obese (BMI >or= 30.0 kg/m(2)), compared with 17.5% and 2.0%, respectively, in the early onset T1DM subgroup. Significant changes in lipid profiles and blood pressure were found with increasing BMI in both the entire population and the early onset T1DM subgroup. In the entire study population HbA1c and the body weight-adjusted daily insulin dose were significantly higher in patients with a BMI >or= 23 kg/m(2) compared with those with a BMI<23 kg/m(2); however, this was not the case in the early onset T1DM subgroup. This difference may be due to the relatively small number of patients in that subgroup. In conclusion, the prevalence of overweight and obesity in patients with T1DM was less than that in the normal Japanese population. For patients with T1DM, being overweight was associated with higher blood pressure and dyslipidemia. Furthermore, we cannot exclude an association between being overweight and the need for higher daily doses of insulin.