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Objectives: Randomised controlled trials are required to address causality in the reported associations between maternal influences and offspring adiposity. The aim of this study was to determine whether an antenatal lifestyle intervention, associated with improvements in maternal diet and reduced gestational weight gain (GWG) in obese pregnant women leads to a reduction in infant adiposity and sustained improvements in maternal lifestyle behaviours at 6 months postpartum., Subjects and Methods: We conducted a planned postnatal follow-up of a randomised controlled trial (UK Pregnancies Better Eating and Activity Trial (UPBEAT)) of a complex behavioural intervention targeting maternal diet (glycaemic load (GL) and saturated fat intake) and physical activity in 1555 obese pregnant women. The main outcome measure was infant adiposity, assessed by subscapular and triceps skinfold thicknesses. Maternal diet and physical activity, indices of the familial lifestyle environment, were assessed by questionnaire., Results: A total of 698 (45.9%) infants (342 intervention and 356 standard antenatal care) were followed up at a mean age of 5.92 months. There was no difference in triceps skinfold thickness z-scores between the intervention vs standard care arms (difference -0.14 s.d., 95% confidence interval -0.38 to 0.10, P=0.246), but subscapular skinfold thickness z-score was 0.26 s.d. (-0.49 to -0.02; P=0.03) lower in the intervention arm. Maternal dietary GL (-35.34; -48.0 to -22.67; P<0.001) and saturated fat intake (-1.93% energy; -2.64 to -1.22; P<0.001) were reduced in the intervention arm at 6 months postpartum. Causal mediation analysis suggested that lower infant subscapular skinfold thickness was partially mediated by changes in antenatal maternal diet and GWG rather than postnatal diet., Conclusions: This study provides evidence from follow-up of a randomised controlled trial that a maternal behavioural intervention in obese pregnant women has the potential to reduce infant adiposity and to produce a sustained improvement in maternal diet at 6 months postpartum.

Background: Higher food intake is implicated in the elevated risk of obesity associated with shorter sleep in children, but the mechanisms driving higher intake are uncertain. Research in adults suggests that acute sleep deprivation affects brain reward systems, which increases responsiveness to palatable foods. However, there have been few studies addressing habitual sleep duration, and few in children, among whom the strongest associations with body mass index (BMI) are seen., Objective: The objective of this study is to test the hypothesis that shorter-sleeping children are more food responsive and explore the mediation of the relationship between sleep and weight by food responsiveness (FR)., Methods: Participants were families from Gemini, a UK twin birth cohort, who had provided complete information on their children's sleep and appetite at age 5 years (n=1008). One child from each twin pair was randomly selected for analyses. Nighttime sleep duration was calculated from parent-reported bedtime and wake time, and categorised as shorter, adequate or longer according to age-specific reference values. FR was assessed with the Child Eating Behaviour Questionnaire. BMI s.d. scores (BMI-SDS) were calculated from parent-measured heights and weights using the UK 1990 reference data and were available for 494 children., Results: There was a significant linear association between shorter sleep and higher FR at age 5 years (P for linear trend=0.032), which was maintained after adjusting for age, sex, birth weight, maternal education and BMI-SDS. In the subset with BMI data at age 5 years, shorter sleep was associated with higher BMI-SDS (P=0.026) as expected. Testing for mediation by adding FR to the model attenuated the linear relationship to borderline significance (P=0.049), suggesting partial mediation., Conclusions: Shorter sleep in childhood is associated with higher FR, which may partly explain the association between shorter sleep and adiposity in childhood.

Objectives: To examine the proportion of normal-weight adolescents who consider themselves to be too heavy (size overestimation), and the proportion of overweight or obese adolescents who consider themselves to be about the right weight or too light (size underestimation), in large population-based samples collected over 8 years in England., Methods: Data were from the Health Survey for England between 2005 and 2012: an annual survey of households representative of the English population. We analysed data from 4979 adolescents (2668 boys, 2311 girls) aged 13 to 15 years old whose weight status was defined as normal weight or overweight/obese based on body mass index standard deviation scores (BMI-SDS) derived from objective measurements of height and weight and using International Obesity Task Force standards. Weight perception was based on the adolescent's choice from the following descriptors: 'about the right weight', 'too heavy' or 'too light'., Results: The majority of normal-weight adolescents (83% of boys, 84% of girls) correctly identified themselves as 'about the right weight'. Overestimation was uncommon, with only 7% of normal-weight teens (4% of boys, 11% of girls) identifying themselves as 'too heavy'. In contrast, only 60% of overweight/obese adolescents (53% of boys, 68% of girls) correctly identified themselves as 'too heavy', whereas 39% (47% of boys, 32% of girls) underestimated, identifying themselves as 'about the right weight' or 'too light'. There were no significant changes in BMI-SDS or body size estimation over time (2005-2012)., Conclusions: Overestimation of body weight among normal-weight adolescents is relatively uncommon; potentially a cause for celebration. However, almost half of boys and a third of girls with a BMI placing them in the overweight or obese BMI range perceived themselves to be about the right weight. Lack of awareness of excess weight among overweight and obese adolescents could be a cause for concern.

Background: Despite a wealth of experimental studies on weight bias, little is known about weight discrimination at the population level. This study examined the prevalence and socio-demographic correlates of perceived weight discrimination in a large population-based sample of older adults., Methods: Data were from 5307 adults in the English Longitudinal Study of Ageing; a population-based cohort of men and women aged ⩾50 years. Weight discrimination was reported for five domains (less respect/courtesy; treated as less clever; poorer treatment in medical settings; poorer service in restaurants/stores; threatened/harassed) at wave 5 (2010-2011). Height and weight were measured at wave 4 (2008-2009). We used logistic regression to test the odds of weight discrimination in relation to weight status, age, sex, wealth, education and marital status., Results: Perceived weight discrimination in any domain was reported by 4.6% of participants, ranging from 0.8% in the normal-weight participants through 0.9, 6.7, 24.2 and 35.1% in individuals who were overweight or met criteria for class I, II and III obesity. Overall, and in each situation, odds of perceived weight discrimination were higher in younger and less wealthy individuals. There was no interaction between weight status and any socio-demographic variable. Relative to normal-weight participants, odds ratios for any perceived weight discrimination were 1.13 (95% confidence interval 0.53-2.40) in those who were overweight, 8.86 (4.65-16.88) in those with class I obesity, 35.06 (18.30-67.16) in class II obese and 56.43 (27.72-114.87) in class III obese., Conclusions: Our results indicate that rates of perceived weight discrimination are comparatively low in individuals who are overweight or have class I obesity, but for those with class II/III obesity, >10% had experienced discrimination in each domain, and >20% had been treated with less respect or courtesy. These findings have implications for public policy and highlight the need for effective interventions to promote equality.

Background and Objectives: Shorter sleep is associated with higher weight in children, but little is known about the mechanisms. The aim of this study was to test the hypothesis that shorter sleep was associated with higher energy intake in early childhood., Methods: Participants were 1303 families from the Gemini twin birth cohort. Sleep duration was measured using the Brief Infant Sleep Questionnaire when the children were 16 months old. Total energy intake (kcal per day) and grams per day of fat, carbohydrate and protein were derived from 3-day diet diaries completed by parents when children were 21 months old., Results: Shorter nighttime sleep was associated with higher total energy intake (P for linear trend=0.005). Children sleeping <10 h consumed around 50 kcal per day more than those sleeping 11-<12 h a night (the optimal sleep duration for children of this age). Differences in energy intake were maintained after adjustment for confounders. As a percentage of total energy intake, there were no significant differences in macronutrient intake by sleep duration. The association between sleep and weight was not significant at this age (P=0.13)., Conclusions: This study provides the first evidence that shorter nighttime sleep duration has a linear association with higher energy intake early in life. That the effect is observed before emergence of associations between sleep and weight indicates that differences in energy intake may be a mechanism through which sleep influences weight gain.

Objective: Infant growth trajectories, in terms of size, tempo and velocity, may programme lifelong obesity risk. Timing of breastfeeding cessation and weaning are both implicated in rapid infant growth; we examined the association of both simultaneously with a range of growth parameters., Design: Longitudinal population-based twin birth cohort., Subjects: The Gemini cohort provided data on 4680 UK infants with a median of 10 (interquartile range=8-15) weight measurements between birth and a median of 6.5 months. Age at breastfeeding cessation and weaning were reported by parents at mean age 8.2 months (s.d.=2.2, range=4-20). Growth trajectories were modelled using SuperImposition by Translation And Rotation (SITAR) to generate three descriptors of individual growth relative to the average trajectory: size (grams), tempo (weeks, indicating the timing of the peak growth rate) and velocity (% difference from average, reflecting mean growth rate). Complex-samples general linear models adjusting for family clustering and confounders examined associations between infant feeding and SITAR parameters., Results: Longer breastfeeding (>4 months vs never) was independently associated with lower growth velocity by 6.8% (s.e.=1.3%) and delayed growth tempo by 1.0 (s.e.=0.2 weeks), but not with smaller size. Later weaning (⩾6 months vs <4 months) was independently associated with lower growth velocity by 4.9% (s.e.=1.1%) and smaller size by 102 g (s.e.=25 g)., Conclusions: Infants breastfed for longer grew slower for longer after birth (later peak growth rate) but were no different in size, while infants weaned later grew slower overall and were smaller but the timing of peak growth did not differ. Slower trajectories with a delayed peak in growth may have beneficial implications for programming later obesity risk. Replication in cohorts with longer follow-up, alternative confounding structures or randomised controlled trials are required to confirm the long-term effects and directionality, and to rule out residual confounding.

Known single-nucleotide polymorphisms (SNPs) explain <2% of the variation in body mass index (BMI) despite the evidence of >50% heritability from twin and family studies, a phenomenon termed 'missing heritability'. Using DNA alone for unrelated individuals, a novel method (in a software package called Genome-wide Complex Trait Analysis, GCTA) estimates the total additive genetic influence due to common SNPs on whole-genome arrays. GCTA has made major inroads into explaining the 'missing heritability' of BMI in adults. This study provides the first GCTA estimate of genetic influence on adiposity in children. Participants were from the Twins Early Development Study (TEDS), a British twin birth cohort. BMI s.d. scores (BMI-SDS) were obtained from validated parent-reported anthropometric measures when children were about 10 years old (mean=9.9; s.d.=0.84). Selecting one child per family (n=2269), GCTA results from 1.7 million DNA markers were used to quantify the additive genetic influence of common SNPs. For direct comparison, a standard twin analysis in the same families estimated the additive genetic influence as 82% (95% CI: 0.74-0.88, P<0.001). GCTA explained 30% of the variance in BMI-SDS (95% CI: 0.02-0.59; P=0.02). These results indicate that 37% of the twin-estimated heritability (30/82%) can be explained by additive effects of multiple common SNPs, and provide compelling evidence for strong genetic influence on adiposity in childhood.

Self-control is generally viewed as highly desirable. In the eating behavior domain, however, the dominance of restraint theory has made the proposition that individuals should attempt to control their eating more controversial. This review discusses evidence from the dietary restraint literature and from studies of self-regulation processes to examine how far self-imposed control around food can be seen as beneficial for effective weight management. Epidemiological and field study evidence provides little support for the proposition that restrained eating causes disinhibited eating patterns. Restraint is often initiated as a response to weight gain, and the co-occurrence of disinhibited and restrained eating patterns on an individual level might better be explained by restraint acting as a marker for overeating tendencies. A sustained effort to monitor and control food intake characterizes successful long-term weight maintenance, suggesting that self-regulation in the eating domain is essential for those with a tendency to gain weight. Evidence from the literature on cognitive self-regulation suggests that there may be potential for people to learn to self-regulate better, both through training and controlled exposure techniques. Integration of the disparate theories of self-regulation is needed to identify the best ways of promoting self-regulation in order to support effective weight control, both in clinical and community settings.

Background: The best outcomes for treating childhood obesity have come from comprehensive family-based programmes. However there are questions over their generalizability., Objective: To examine the acceptability and effectiveness of 'family-based behavioural treatment' (FBBT) for childhood obesity in an ethnically and socially diverse sample of families in a UK National Health Service (NHS) setting., Methods: In this parallel group, randomized controlled trial, 72 obese children were randomized to FBBT or a waiting-list control. Primary outcomes were body mass index (BMI) and BMI s.d. scores (SDSs). Secondary outcomes were weight, weight SDSs, height, height SDSs, waist, waist SDSs, FM index, FFM index, blood pressure (BP) and psychosocial measures. The outcomes were assessed at baseline and after treatment, with analyses of 6-month data performed on an intent-to-treat (ITT) basis. Follow-up anthropometric data were collected at 12 months for the treatment group., Results: ITT analyses included all children with baseline data (n=60). There were significant BMI SDS changes (P<0.01) for the treatment and control groups of -0.11 (0.16) and -0.10 (1.6). The treatment group showed a significant reduction in systolic BP (-0.24 (0.7), P<0.05) and improvements in quality of life and eating attitudes (P<0.05), with no significant changes for the control group. However the between-group treatment effects for BMI, body composition, BP and psychosocial outcomes were not significant. There was no overall change in BMI or BMI SDSs from 0-12 months for the treatment group. No adverse effects were reported., Conclusions: Both treatment and control groups experienced significant reductions in the level of overweight, but with no significant difference between them. There were no significant group differences for any of the secondary outcomes. This trial was registered at http://www.controlled-trials.com/ under ISRCTN 51382628.

Context: The association between low socioeconomic status (SES) and childhood obesity foreshadows lifelong inequalities in health. Insight into the causal mechanisms linking childhood adversity to long-term health could be provided by discovering when the negative SES gradient in weight emerges and what early life experiences are associated with it., Objective: SES differences in infant weight gain in the first 3 months of life were examined, and contributions of parental body mass index, maternal smoking and feeding method to this association were assessed., Design: Observational study using longitudinal weight data from 2402 families taking part in the Gemini Study; a twin birth cohort recruited from all twin births between March and December 2007 in England and Wales., Outcome Measures: Infant weights at birth and 3 months converted to standard deviation scores (SDS), change in weight SDS and rapid growth. SES was indexed by occupation and maternal education., Results: There were no SES differences in birth weight, but lower SES was associated with higher 3-month weight, greater change in weight and a higher prevalence of rapid growth (all P < 0.01), with graded associations across levels of SES. Including parental overweight or smoking in pregnancy in the regression model did not affect the association between SES and weight gain, but including feeding method attenuated the SES effect on weight gain by at least 62% and rendered it nonsignificant., Conclusion: The foundations for lifelong socioeconomic inequalities in obesity risk may be laid in early infancy, with infant-feeding practices having a part in the diverging weight trajectories.

Objective: Previous data indicate a rapidly increasing prevalence of obesity and overweight among English children and an emerging socioeconomic gradient in prevalence. The main aim of this study was to update the prevalence trends among school-age children and assess the changing socioeconomic gradient., Design: A series of nationally representative household-based health surveys conducted between 1997 and 2007 in England., Subjects: 15 271 white children (7880 boys) aged 5 to 10 years with measured height and weight., Measurements: Height and weight were directly measured by trained fieldworkers. Overweight (including obesity) and obesity prevalence were calculated using the international body mass index cut-offs. Socioeconomic position (SEP) score was a composite score based on income and social class. Multiple linear regression assessed the prevalence odds with time point (1997/8, 2000/1, 2002/3, 2004/5, 2006/7) as the main exposure. Linear interaction terms of time by SEP were also tested for., Results: There are signs that the overweight and obesity trend has levelled off from 2002/3 to 2006/7. The odds ratio (OR) for overweight in 2006/7 compared with 2002/3 was 0.99 (95% CI 0.88-1.11) and for obesity OR = 1.06 (0.86-1.29). The socioeconomic gradient has increased in recent years, particularly in 2006/7. Compared to 1997/8, the 2006/7 age and sex-adjusted OR for overweight was 1.88 (1.52 to 2.33) in low-SEP, 1.25 (1.04 to 1.50) in middle-SEP, and 1.13 (0.86 to 1.48) in high-SEP children., Conclusion: Childhood obesity and overweight prevalence among school-age children in England has stabilized in recent years, but children from lower socio-economic strata have not benefited from this trend. There is an urgent need to reduce socio-economic disparities in childhood overweight and obesity.

Objective: It is important to understand levels and social inequalities in childhood overweight within and between countries. This study examined prevalence and social inequality in adolescent overweight in 35 countries, and associations with macroeconomic factors., Design: International cross-sectional survey in national samples of schools., Subjects: A total of 11-, 13- and 15-year-olds from 35 countries in Europe and North America in 2001-2002 (N=162 305)., Measurements: The main outcome measure was overweight based on self-reported height and weight (body mass index cut-points corresponding to body mass index of 25 kg/m(2) at the age of 18 years). Measures included family and school affluence (within countries), and average country income and economic inequality (between countries)., Results: There were large variations in adolescent overweight, from 3.5% in Lithuanian girls to 31.7% in boys from Malta. Prevalence of overweight was higher among children from less affluent families in 21 of 24 Western and 5 of 10 Central European countries. However, children from more affluent families were at higher risk of overweight in Croatia, Estonia and Latvia. In Poland, Lithuania, Macedonia and Finland, girls from less affluent families were more overweight whereas the opposite was found for boys. Average country income was associated with prevalence and inequality in overweight when considering all countries together. However, economic inequality as measured by the Gini coefficient was differentially associated with prevalence and socioeconomic inequality in overweight among the 23-high income and 10-middle income countries, with a positive relationship among the high income countries and a negative association among the middle income countries., Conclusion: The direction and magnitude of social inequality in adolescent overweight shows large international variation, with negative social gradients in most countries, but positive social gradients, especially for boys, in some Central European countries. Macroeconomic factors are associated with the heterogeneity in prevalence and social inequality of adolescent overweight.

Objective: Polymorphisms in the obesity-associated gene, FTO, have been linked with sensitivity to satiety in children, indicating FTO may be influencing one of the regulatory drivers underlying food intake. In this study, we tested the hypothesis that food intake in a standard eating behaviour paradigm in which palatable food is offered under conditions of satiety would be associated with FTO genotype status, after controlling for differences in body mass index (BMI)., Methods: Participants were 131 children aged 4-5 years, taking part in a behavioural study of food intake for whom DNA was available for genotyping. The phenotypic indicator of intake was the child's consumption of palatable food presented after having eaten a meal. We also assessed physical activity using parental reports of the child's enjoyment of active games, their level of activity relative to other children and a standard measure of fidgetiness. Associations between polymorphisms of the intronic FTO single nucleotide polymorphism (rs9939609) and behaviour (food intake and activity) were assessed by analysis of variance controlling for sex, age and BMI s.d. scores., Results: The distribution of AA (homogenous for A allele), AT (heterogeneous T and A alleles) and TT (homogenous for T allele) genotypes was 18, 50 and 32%, respectively. As predicted, TT homozygotes ate significantly less than heterozygotes (P=0.03) or AA homozygotes (P=0.02). The effect was not diminished by controlling for BMI s.d. scores. There were no significant associations between FTO genotype and any marker of physical activity., Conclusions: We showed that children with two copies of the lower-risk FTO alleles ate less than those with one or two higher-risk alleles. We conclude that the T allele is protective against overeating by promoting responsiveness to internal signals of satiety.

Objective: To test the hypothesis that quantitative variation in eating behaviour traits shows a graded association with weight in children., Design: Cross-sectional design in a community setting., Subjects: Data were from 406 families participating in the Physical Exercise and Appetite in CHildren Study (PEACHES) or the Twins Early Development Study (TEDS). Children were aged 7-9 years (PEACHES) and 9-12 years (TEDS)., Measurements: Weights and heights were measured by researchers. Body mass index (BMI) s.d. scores were used to categorize participants into underweight, healthy weight, overweight and obese groups, with an additional division of the healthy weight group into higher and lower healthy weight at the 50th centile. Eating behaviour traits were assessed with the Child Eating Behaviour Questionnaire (CEBQ), completed by the parents on behalf of their child. Linear trend analyses compared CEBQ subscale scores across the five weight groups., Results: Satiety Responsiveness/Slowness in Eating and Food Fussiness showed a graded negative association with weight, whereas Food Responsiveness, Enjoyment of Food, Emotional Overeating and Desire to Drink were positively associated. All effects were maintained after controlling for age, sex, ethnicity, parental education and sample. There was no systematic association with weight for Emotional Undereating., Conclusion: These results support the idea that approach-related and avoidance-related appetitive traits are systematically (and oppositely) related to adiposity, and not exclusively associated with obesity. Early assessment of these traits could be used as indicators of susceptibility to weight gain.

Objective: To examine the association between eating in the absence of hunger (EAH) and adiposity in children., Design: Two cross-sectional studies in community settings., Subjects: For study 1, 348 children (178 girls and 170 boys) aged 7-9 years were recruited as part of the Physical Exercise and Appetite in Children Study. In study 2, participants were a subsample of children aged 9-12 years (N=316; 192 girls and 124 boys) from the Twins Early Development Study., Measurements: EAH was operationalized as intake of highly palatable sweet snacks after a mixed meal at school (study 1) or home (study 2). Weight (kg) and height (m) measurements were used to calculate the body mass index (BMI) s.d. scores. Children were grouped using the standard criteria for underweight, healthy weight, overweight and obesity. The healthy weight range was further subdivided into lower healthy weight (50th centile) to examine the distribution of EAH across the adiposity continuum., Results: In both studies, EAH showed a significant positive association with adiposity in boys after adjusting for covariates (P<0.001), with a linear increase in the intake across underweight, healthy weight and overweight groups. The association between EAH and adiposity was not significant in girls in either study, although in study 1, results showed a quadratic trend, with EAH increasing through the underweight and healthy weight ranges and decreasing in overweight and obese groups., Conclusion: EAH is a behavioural phenotype that is not specific to overweight children but instead shows a graded association with adiposity across the weight continuum, particularly in boys. In this study, the effect was less pronounced in girls, which may reflect social desirability pressures constraining food intake among heavier girls.

Background: The modern environment is ubiquitously 'obesogenic', yet people vary enormously in weight. One factor contributing to weight variation could be genetically determined differences in appetite that modulate susceptibility to the environment. We assessed the relative contribution of genes and environment for two aspects of appetite that have been implicated in obesity., Methods: Parents of a population-based sample of 8- to 11-year-old twins (n=5435 pairs) completed validated, questionnaire measures of responsiveness to satiety and responsiveness to food cues for both children., Results: Quantitative genetic model fitting gave estimates of 63% (95% confidence interval: 39-81%) for the heritability of satiety responsiveness and 75% (52-85%) for food cue responsiveness. Shared and non-shared environmental influences were 21% (0-51%) and 16% (10-21%) for satiety responsiveness, and 10% (0-38%) and 15% (10-18%) for food cue responsiveness, respectively., Conclusions: The high heritability of appetitive traits that are known to be related to weight suggests that genetic vulnerability to weight gain could operate through behavioural as well as metabolic pathways. Intervention strategies aimed at improving satiety responsiveness and reducing food cue responsiveness in high-risk individuals could help in preventing the development of obesity.

Objective: To evaluate the efficacy of a simple weight loss intervention, based on principles of habit formation., Design: An exploratory trial in which overweight and obese adults were randomized either to a habit-based intervention condition (with two subgroups given weekly vs monthly weighing; n=33, n=36) or to a waiting-list control condition (n=35) over 8 weeks. Intervention participants were followed up for 8 months., Participants: A total of 104 adults (35 men, 69 women) with an average BMI of 30.9 kg m(-2)., Intervention: Intervention participants were given a leaflet containing advice on habit formation and simple recommendations for eating and activity behaviours promoting negative energy balance, together with a self-monitoring checklist., Main Outcome Measures: Weight change over 8 weeks in the intervention condition compared with the control condition and weight loss maintenance over 32 weeks in the intervention condition., Results: At 8 weeks, people in the intervention condition had lost significantly more weight (mean=2.0 kg) than those in the control condition (0.4 kg), with no difference between weekly and monthly weighing subgroups. At 32 weeks, those who remained in the study had lost an average of 3.8 kg, with 54% losing 5% or more of their body weight. An intention-to-treat analysis (based on last-observation-carried-forward) reduced this to 2.6 kg, with 26% achieving a 5% weight loss., Conclusions: This easily disseminable, low-cost, simple intervention produced clinically significant weight loss. In limited resource settings it has potential as a tool for obesity management.

Background: Obesity rates have increased markedly in recent years. This study investigated whether increases in adiposity over the past 10 years in England reflect across-the-board gains in adiposity or differential effects in subgroups., Methods: The data were from the Health Surveys for England, which include home-based measurements of height, weight and waist circumference in population-representative samples. Mean-difference (m-d) curves were calculated to examine increases in BMI and central adiposity at selected percentile points across the distribution between 1993/4 and 2002/3. The sample comprised 20,246 participants in 1993/1994 and 11 708 in 2002/2003. Patterning of population adiposity was examined in relation to gender, age and socioeconomic status (SES)., Results: Both BMI and central adiposity increased markedly more in the upper part of the distribution, with intermediate increases in the middle and little change at the lower end of the distribution. The patterning and magnitude of increases in adiposity were similar for men and women, and for lower and higher SES groups. Increases at the top of the distribution were greater for younger adults, with the 90th percentile of waist circumference increasing by more than 8 cm in 10 years in young women., Conclusions: Gains in adiposity have not been equivalent across the BMI distribution. Thinner people in 2002/3 were almost as thin as they were 10 years earlier, but fatter people were considerably fatter. This could represent progressively greater responsiveness to the 'obesogenic' environment in individuals with higher complements of susceptibility genes. These population trends have important implications for future health and services to manage severe obesity.

Background: Evidence suggests that people who are more responsive to psychological stress are at an increased risk of developing obesity. However, the biological mechanisms underlying this phenomenon are poorly understood. The cytokines leptin, interleukin-1 receptor antagonist (IL-1Ra) and interleukin-6 (IL-6) play a key role in fat metabolism and abnormal circulating levels of these proteins have been reported in obese people and in individuals subject to stress., Objective: This study investigated whether cytokine responses to acute mental stress are associated with adiposity in healthy young women., Design and Subjects: A laboratory study of 67 women, aged 18-25 years, recruited from University College London., Measurements: Height, weight and waist circumference were measured and body fat mass was estimated by bioelectrical impedance body composition analysis. Laboratory mental stress testing was carried out and blood pressure and heart rate were recorded at baseline, during two moderately challenging tasks (Stroop and speech) and during recovery 40-45 min post-stress. Blood samples taken at baseline, immediately post-stress and 45 min post-stress, were used for assessment of circulating cytokines. Saliva samples taken throughout the session were assessed for cortisol., Results: Women who had larger cytokine responses to stress were more abdominally obese than women with smaller cytokine stress responses. Specifically, there was a positive correlation between waist circumference and stress-induced increases in plasma levels of leptin (r=0.35, P<0.05) and IL-1Ra responses (r=0.29, P<0.05). There was also a significant positive correlation between prolonged diastolic blood pressure responses to stress and measures of total and abdominal obesity (r=0.28-0.33, P<0.05)., Conclusion: Increased cytokine production could be a mechanism linking stress and abdominal obesity.

Objective: School-based physical education (PE) is often proposed as a strategy for obesity prevention, but many trials have found non-significant effects on body mass index (BMI). We examined the impact of school PE on adiposity in adolescents, using an ecological analysis to relate the number of PE sessions to changes in BMI and waist circumference., Research Methods and Procedures: Five-year, longitudinal, school-based study involving 34 secondary schools in London, England. Students were aged 11-12 years at baseline. Twenty-five schools reported one weekly session of PE, seven schools reported two sessions and two boys' schools reported three sessions. Weights, heights and waist circumferences were measured annually, and complete data from the first and fifth years of the study were available on 2727 students. Analyses compared anthropometric changes between students in schools with higher or lower amounts of PE time. In boys, the comparisons were between those receiving 1, 2 or 3 weekly sessions. In girls, comparisons were between those receiving one and two sessions., Results: There were no differences in BMI changes or the percentage of students classified as obese between schools of higher and lower frequency of PE. However, using unadjusted data, there were lower gains in waist circumference in boys and girls from the higher PE schools. Controlling for baseline demographic and anthropometric characteristics, boys in schools providing 3 weekly PE sessions gained on average approximately 3 cm less than boys in schools providing one or two sessions (P<0.001). Differences in girls were in the same direction but not significant., Discussion: Higher levels of school PE were associated with lower gains in adiposity in boys. This strengthens the case for including recommendations on school PE time as part of population strategies to control adolescent obesity.

Objective: Young women in the United States and Western Europe are notoriously concerned about weight but less is known about attitudes to weight in other regions of the world. This study explores the associations between body mass index (BMI), weight perceptions, and attempts to lose weight in male and female university students from 22 countries., Methods: Data were collected from 18,512 university students, using standardised methods, as part of the International Health Behaviour Survey. Measures included weight, height, perception of overweight, and weight loss status. BMI was calculated from weight and height, but was categorised into gender and country-standardised deciles rather than the conventional weight categories in response to the inaccuracy of self-reports. Perceived overweight and weight loss status were plotted against country-standardised BMI deciles. The 22 countries were grouped into five geopolitical/economic areas for regional analyses: North-Western Europe and the USA, Central and Eastern Europe, the Mediterranean, Pacific Asia, South America. Perceived overweight compared across the five regions., Results: Perceived overweight increased systematically across BMI deciles in all countries. More women than men felt overweight at any decile. Women had low levels of perceived overweight in the lowest decile but rates rapidly increased to 50% by the 5th decile. Men, even in the highest deciles, were less aware that they are overweight and few of them were trying to lose weight. Women had a faster rise of weight loss attempts over the BMI deciles but nevertheless the proportion trying to lose in the highest decile did not exceed 75%. Perceived overweight profiles across BMI deciles were similar across all regions, suggesting that perceptions of overweight derive from local comparisons. The patterning for trying to lose weight was more diverse, with men and women from Asian countries showing higher levels of trying to lose weight at all deciles., Conclusions: This study shows the international consistency in perceptions of overweight in educated young men and women across diverse regions of the world. It confirms the patterning of women's overestimation of weight at lower BMI deciles and men's underestimation of weight at the higher deciles. Perceptions of overweight and attempts to lose weight were highest in the group of Asian countries where body weights are generally low, suggesting that local culture and norms could moderate attitudes to weight.

Objective: Community studies relating depression to obesity in adolescents have generated inconsistent results. It has been argued that the variability in findings is due to effect modification by demographic characteristics that vary across samples. The aim of this study was to test the hypothesis that the strength of the obesity-depression association is moderated by gender, ethnicity and socioeconomic status (SES)., Research Methods and Procedures: Data were from two large, school-based, studies of adolescent health and well-being (n=4320; n=1824). Students completed one of two measures of depressive symptoms (SDQ; CES-D) in school and were weighed and measured. Gender and ethnicity were self-reported and SES was indexed by residential neighbourhood characteristics or individual family deprivation., Results: There was barely any association between obesity and depressive symptoms in either sample. There was also no evidence that obese participants who were female, white or from higher SES backgrounds were especially vulnerable to depressive symptoms., Discussion: The results indicate that in community samples of adolescents, regardless of gender, SES or ethnicity, reports of depressive symptoms are not significantly higher in obese than normal-weight groups. The results are discussed in terms of obese adolescents' resilience in the face of multiple social adversities.

Objective: To assess the relationship between adiposity and cardiovascular stress reactivity and recovery in middle-aged men and women, and investigate the influence of impaired poststress cardiovascular recovery on changes in body mass index (BMI) and waist-hip ratio over 3 y., Participants: In total, 225 healthy men and women aged 47-59 y were recruited from the British civil service., Methods: Laboratory mental stress testing was carried out, with blood pressure (BP), cardiac output and total peripheral resistance being measured at baseline, during moderately challenging tasks, and during recovery 40-45 min poststress. Weight, height, waist and hip circumference were assessed at the time of mental stress testing and 3 y later., Results: Behavioural tasks elicited increases in BP sustained by a combination of cardiac activation and raised peripheral resistance. BMI and waist/hip ratio were associated cross-sectionally with impaired poststress recovery of systolic pressure, diastolic pressure and cardiac index independently of age, gender, socioeconomic status, smoking, alcohol consumption and baseline cardiovascular activity. Increases in waist-hip ratio over 3 y were predicted both by impaired poststress recovery of systolic pressure and cardiac index in men, independently of baseline adiposity and other covariates. No associations between subjective stress and BMI or waist-hip ratio were observed., Conclusions: Disturbances of cardiovascular responsivity to psychological stress, manifest through impaired poststress recovery, were associated cross-sectionally with BMI, and longitudinally with central adiposity in men. Stress-related cardiovascular dysregulation may contribute to obesity risk.

Objective: To assess the accuracy of parents' perceptions of their 3 to 5 y old children's weight status in a large UK sample., Method: Parental perception and concern about child weight, demographic variables, and children's height and weight were obtained for 564 parent-child dyads., Results: Only 1.9% of parents of overweight children and 17.1% of parents of obese children described their child as overweight. The odds of parents perceiving the child as overweight were increased for overweight (2.7; 95% CI 0.4, 16.5) and obese (28.5; 7.1, 115.4) compared with normal weight children, but were not associated with parental weight or with any demographic factors. Although few parents perceived their overweight children as overweight, more (66.2%) expressed concern about their overweight child becoming overweight in the future. Odds of concern were progressively higher for overweight (2.5; 1.6, 3.9) and obese children (4.6; 2.2, 9.7), and were also higher for parents who were themselves overweight (1.9; 1.2, 2.9) or obese (2.5; 1.3, 4.8)., Conclusion: These findings suggest that parents of 3-5 y olds show poor awareness of their child's current weight status. Reframing discussions in terms of preventing future overweight may be an effective way to engage parents.