Use of Evidence-Based Interventions to Promote Healthy Weight, Nutrition, and Physical Activity in Community Health Improvement Plans from Large Local Health Departments.

We sought to identify evidence-based healthy weight, nutrition, and physical activity strategies related to obesity prevention in large local health department (LHD) Community Health Improvement Plans (CHIPs). We analyzed the content of the most recent, publicly available plans from 72 accredited LHDs serving a population of at least 500 000 people. We matched CHIP strategies to the County Health Rankings and Roadmaps' What Works for Health (WWFH) database of interventions. We identified 739 strategies across 55 plans, 62.5% of which matched a "WWFH intervention" rated for effectiveness on diet and exercise outcomes. Among the 20 most commonly identified WWFH interventions in CHIPs, 10 had the highest evidence for effectiveness while 4 were rated as likely to decrease health disparities according to WWFH. Future prioritization of strategies by health agencies could focus on strategies with the strongest evidence for promoting healthy weight, nutrition, and physical activity outcomes and reducing health disparities.

Excess mortality associated with elevated body weight in the USA by state and demographic subgroup: A modelling study.

Background: The obesity epidemic in the USA continues to grow nationwide. Although excess weight-related mortality has been studied in general, less is known about how it varies by demographic subgroup within the USA. In this study we estimated excess mortality associated with elevated body weight nationally and by state and subgroup. Methods: We developed a nationally-representative microsimulation (individual-level) model of US adults between 1999 and 2016, based on risk factor data from 6,002,012 Behavioral Risk Factor Surveillance System respondents. Prior probability distributions for hazard ratios relating body-mass index (BMI) to mortality were informed by a global pooling dataset. Individual-level mortality risks were modelled accounting for demographics, smoking history, and BMI adjusted for self-report bias. We calibrated the model to empirical all-cause mortality rates from CDC WONDER by state and subgroup, and assessed the predictive accuracy of the model using a random sample of data withheld from model fitting. We simulated counterfactual scenarios to estimate excess mortality attributable to different levels of excess weight and smoking history. Findings: We estimated that excess weight was responsible for more than 1300 excess deaths per day (nearly 500,000 per year) and a loss in life expectancy of nearly 2·4 years in 2016, contributing to higher excess mortality than smoking. Relative excess mortality rates were nearly twice as high for women compared to men in 2016 (21·9% vs 13·9%), and were higher for Black non-Hispanic adults. By state, overall excess weight-related life expectancy loss ranged from 1·75 years (95% UI 1·57-1·94) in Colorado to 3·18 years (95% UI 2·86-3·51) in Mississippi. Interpretation: Excess weight has substantial impacts on mortality in the USA, with large disparities by state and subgroup. Premature mortality will likely increase as obesity continues to rise. Funding: The JPB Foundation, NIH, CDC.

Assessing the effectiveness of training models for national scale-up of an evidence-based nutrition and physical activity intervention: a group randomized trial.

BACKGROUND: There is a great need to identify implementation strategies to successfully scale-up public health interventions in order to achieve their intended population impact. The Out-of-school Nutrition and Physical Activity group-randomized trial previously demonstrated improvements in children's vigorous physical activity and the healthfulness of foods and beverages consumed. This implementation study aimed to assess the effects and costs of two training models to scale-up this evidence-based intervention. METHODS: A 3-arm group-randomized trial was conducted to compare effectiveness of in-person and online training models for scaling up the intervention compared to controls. One-third of sites were randomized to the in-person train-the-trainer model: local YMCA facilitators attended a training session and then conducted three learning collaborative meetings and technical assistance. One-third were assigned to the online model, consisting of self-paced monthly learning modules, videos, quizzes, and facilitated discussion boards. Remaining sites served as controls. Fifty-three afterschool sites from three YMCA Associations in different regions of the country completed baseline and follow-up observations using a validated tool of afterschool nutrition and physical activity practices. We used multivariable regression models, accounting for clustering of observations, to assess intervention effects on an aggregate afterschool practice primary outcome, and conducted secondary analyses of nine intervention goals (e.g. serving water). Cost data were collected to determine the resources to implement each training model. RESULTS: Changes in the primary outcome indicate that, on average, sites in the in-person arm achieved 0.44 additional goals compared to controls (95%CI 0.02, 0.86, p = 0.04). Increases in the number of additional goals achieved in sites in the online arm were not significantly greater than control sites (+ 0.28, 95% CI -0.18, 0.73, p = 0.24). Goal-specific improvements were observed for increasing water offered in the in-person arm and fruits and vegetables offered in the online arm. The cost per person trained was $678 for the in-person training model and $336 for the on-line training model. CONCLUSIONS: This pilot trial presents promising findings on implementation strategies for scale-up. It validated the in-person training model as an effective approach. The less expensive online training may be a useful option for geographically disbursed sites where in-person training is challenging. TRIAL REGISTRATION: Although this study does not report the results of a health care intervention on human subjects, it is a randomized trial and was therefore retrospectively registered in ClinicalTrials.gov on July 4, 2019 in accordance with the BMC guidelines to ensure the complete publication of all results (NCT04009304).

Impact of the Out-of-School Nutrition and Physical Activity (OSNAP) Group Randomized Controlled Trial on Children's Food, Beverage, and Calorie Consumption among Snacks Served.

BACKGROUND: Afterschool interventions have been found to improve the nutritional quality of snacks served. However, there is limited evidence on how these interventions affect children's snacking behaviors. OBJECTIVE: Our aim was to determine the impact of an afterschool intervention focused at the school district, site, family, and child levels on dietary consumption of foods and beverages served at snack. DESIGN: This was a secondary analysis of a group-randomized controlled trial. PARTICIPANTS/SETTING: Data were collected from 400 children at 20 afterschool sites in Boston, MA before (fall 2010) and after (spring 2011) intervention implementation. INTERVENTION: The Out-of-School Nutrition and Physical Activity intervention aimed to promote fruits, vegetables, whole grains, and water, while limiting sugary drinks and trans fats. Researchers worked with district foodservice staff to change snack foods and beverages. Teams of afterschool staff participated in three 3-hour learning collaborative sessions to build skills and created action plans for changing site practices. The intervention included family and child nutrition education. MAIN OUTCOME MEASURES: Research assistants observed dietary snack consumption using a validated measure on 2 days per site at baseline and follow-up. STATISTICAL ANALYSES PERFORMED: This study used multivariable regression models, accounting for clustering of observations, to assess the intervention effect, and conducted post-hoc stratified analyses by foodservice type. RESULTS: Children in intervention sites had greater decreases in consumption of juice (-0.61 oz/snack, 95% CI -1.11 to -0.12), beverage calories (-29.1 kcal/snack, 95% CI -40.2 to 18.0), foods with trans fats (-0.12 servings/snack, 95% CI -0.19 to -0.04), total calories (-47.7 kcal/snack, 95% CI -68.2 to -27.2), and increases in consumption of whole grains (0.10 servings/snack, 95% CI 0.02 to 0.18) compared to controls. In post-hoc analyses, sites with on-site foodservice had significant improvements for all outcomes (P<0.001), with no effect for sites with satellite foodservice. CONCLUSIONS: Results demonstrate that an afterschool intervention can improve children's dietary snack consumption, particularly at sites with on-site foodservice.

United States Adolescents' Television, Computer, Videogame, Smartphone, and Tablet Use: Associations with Sugary Drinks, Sleep, Physical Activity, and Obesity.

OBJECTIVE: To quantify the relationships between youth use of television (TV) and other screen devices, including smartphones and tablets, and obesity risk factors. STUDY DESIGN: TV and other screen device use, including smartphones, tablets, computers, and/or videogames, was self-reported by a nationally representative, cross-sectional sample of 24 800 US high school students (2013-2015 Youth Risk Behavior Surveys). Students also reported on health behaviors including sugar-sweetened beverage (SSB) intake, physical activity, sleep, and weight and height. Sex-stratified logistic regression models, adjusting for the sampling design, estimated associations between TV and other screen device use and SSB intake, physical activity, sleep, and obesity. RESULTS: Approximately 20% of participants used other screen devices for ≥5 hours daily. Watching TV ≥5 hours daily was associated with daily SSB consumption (aOR = 2.72, 95% CI: 2.23, 3.32) and obesity (aOR = 1.78, 95% CI: 1.40, 2.27). Using other screen devices ≥5 hours daily was associated with daily SSB consumption (aOR = 1.98, 95% CI: 1.69, 2.32), inadequate physical activity (aOR = 1.94, 95% CI: 1.69, 2.25), and inadequate sleep (aOR = 1.79, 95% CI: 1.54, 2.08). CONCLUSIONS: Using smartphones, tablets, computers, and videogames is associated with several obesity risk factors. Although further study is needed, families should be encouraged to limit both TV viewing and newer screen devices.

New Strategies to Prioritize Nutrition, Physical Activity, and Obesity Interventions.

Interventions for obesity have not often been based on considerations that could predict their effectiveness. However, advances in research provide several new approaches that can inform priorities for public health interventions directed at nutrition, physical activity, and obesity. These approaches include estimation of the effect size, comparison of the calorie gap with the caloric deficit induced by the intervention, population reach and impact, cost and cost effectiveness of the intervention, time required to evaluate the effect of the intervention on weight change, and feasibility of the intervention. Incorporation of these considerations by policymakers and public health practitioners will help identify those interventions most likely to achieve changes in the prevalence of obesity.

Promoting Physical Activity With the Out of School Nutrition and Physical Activity (OSNAP) Initiative: A Cluster-Randomized Controlled Trial.

IMPORTANCE: Millions of children attend after-school programs in the United States. Increasing physical activity levels of program participants could have a broad effect on children's health. OBJECTIVE: To test the effectiveness of the Out of School Nutrition and Physical Activity (OSNAP) Initiative in increasing children's physical activity levels in existing after-school programs. DESIGN, SETTING, AND PARTICIPANTS: Cluster-randomized controlled trial with matched program pairs. Baseline data were collected September 27 through November 12, 2010, with follow-up data collected April 25 through May 27, 2011. The dates of our analysis were March 11, 2014, through August 18, 2015. The setting was 20 after-school programs in Boston, Massachusetts. All children 5 to 12 years old in participating programs were eligible for study inclusion. INTERVENTIONS: Ten programs participated in a series of three 3-hour learning collaborative workshops, with additional optional opportunities for training and technical assistance. MAIN OUTCOMES AND MEASURES: Change in number of minutes and bouts of moderate to vigorous physical activity, vigorous physical activity, and sedentary activity and change in total accelerometer counts between baseline and follow-up. RESULTS: Participants with complete data were 402 racially/ethnically diverse children, with a mean age of 7.7 years. Change in the duration of physical activity opportunities offered to children during program time did not differ between conditions (-1.2 minutes; 95% CI, -14.2 to 12.4 minutes; P = .87). Change in moderate to vigorous physical activity minutes accumulated by children during program time did not differ significantly by intervention status (-1.0; 95% CI, -3.3 to 1.3; P = .40). Total minutes per day of vigorous physical activity (3.2; 95% CI, 1.8-4.7; P < .001), vigorous physical activity minutes in bouts (4.1; 95% CI, 2.7-5.6; P < .001), and total accelerometer counts per day (16,894; 95% CI, 5101-28,686; P = .01) increased significantly during program time among intervention participants compared with control participants. CONCLUSIONS AND RELEVANCE: Although programs participating in the OSNAP Initiative did not allot significantly more time for physical activity, they successfully made existing time more vigorously active for children receiving the intervention. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01396473.

Severe Obesity In Adults Cost State Medicaid Programs Nearly $8 Billion In 2013.

Efforts to expand Medicaid while controlling spending must be informed by a deeper understanding of the extent to which the high medical costs associated with severe obesity (having a body mass index of [Formula: see text] or higher) determine spending at the state level. Our analysis of population-representative data indicates that in 2013, severe obesity cost the nation approximately $69 billion, which accounted for 60 percent of total obesity-related costs. Approximately 11 percent of the cost of severe obesity was paid for by Medicaid, 30 percent by Medicare and other federal health programs, 27 percent by private health plans, and 30 percent out of pocket. Overall, severe obesity cost state Medicaid programs almost $8 billion a year, ranging from $5 million in Wyoming to $1.3 billion in California. These costs are likely to increase following Medicaid expansion and enhanced coverage of weight loss therapies in the form of nutrition consultation, drug therapy, and bariatric surgery. Ensuring and expanding Medicaid-eligible populations' access to cost-effective treatment for severe obesity should be part of each state's strategy to mitigate rising obesity-related health care costs.

Three Interventions That Reduce Childhood Obesity Are Projected To Save More Than They Cost To Implement.

Policy makers seeking to reduce childhood obesity must prioritize investment in treatment and primary prevention. We estimated the cost-effectiveness of seven interventions high on the obesity policy agenda: a sugar-sweetened beverage excise tax; elimination of the tax subsidy for advertising unhealthy food to children; restaurant menu calorie labeling; nutrition standards for school meals; nutrition standards for all other food and beverages sold in schools; improved early care and education; and increased access to adolescent bariatric surgery. We used systematic reviews and a microsimulation model of national implementation of the interventions over the period 2015-25 to estimate their impact on obesity prevalence and their cost-effectiveness for reducing the body mass index of individuals. In our model, three of the seven interventions--excise tax, elimination of the tax deduction, and nutrition standards for food and beverages sold in schools outside of meals--saved more in health care costs than they cost to implement. Each of the three interventions prevented 129,000-576,000 cases of childhood obesity in 2025. Adolescent bariatric surgery had a negligible impact on obesity prevalence. Our results highlight the importance of primary prevention for policy makers aiming to reduce childhood obesity.

Impact of implementation factors on children's water consumption in the Out-of-School Nutrition and Physical Activity group-randomized trial.

National data suggest that children are not consuming enough water. Experimental evidence has linked increased water consumption to obesity prevention, and the National AfterSchool Association has named serving water as ones of its standards for healthy eating and physical activity in out-of-school time settings. From fall 2010 to spring 2011, twenty Boston afterschool program sites participated in the Out-of-School Nutrition and Physical Activity (OSNAP) initiative, a group-randomized trial investigating nutrition and physical activity policies and practices that promote child health. Researchers used data from OSNAP to study the key factors that influence the implementation of practices that promote water intake. Aspects of the organizational capacity of the afterschool programs, characteristics of the providers, and the community context were hypothesized to impact changes in children's water consumption. This chapter demonstrates the effectiveness of an afterschool intervention on increases in children's water consumption. It also outlines the substantial influence that implementation factors can have on the effectiveness of an obesity prevention intervention, highlighting the importance of understanding how interventions are delivered in real-world settings.

Validity of a practitioner-administered observational tool to measure physical activity, nutrition, and screen time in school-age programs.

BACKGROUND: Nutrition and physical activity interventions have been effective in creating environmental changes in afterschool programs. However, accurate assessment can be time-consuming and expensive as initiatives are scaled up for optimal population impact. This study aims to determine the criterion validity of a simple, low-cost, practitioner-administered observational measure of afterschool physical activity, nutrition, and screen time practices and child behaviors. METHODS: Directors from 35 programs in three cities completed the Out-of-School Nutrition and Physical Activity Observational Practice Assessment Tool (OSNAP-OPAT) on five days. Trained observers recorded snacks served and obtained accelerometer data each day during the same week. Observations of physical activity participation and snack consumption were conducted on two days. Correlations were calculated to validate weekly average estimates from OSNAP-OPAT compared to criterion measures. Weekly criterion averages are based on 175 meals served, snack consumption of 528 children, and physical activity levels of 356 children. RESULTS: OSNAP-OPAT validly assessed serving water (r = 0.73), fruits and vegetables (r = 0.84), juice >4oz (r = 0.56), and grains (r = 0.60) at snack; sugary drinks (r = 0.70) and foods (r = 0.68) from outside the program; and children's water consumption (r = 0.56) (all p <0.05). Reports of physical activity time offered were correlated with accelerometer estimates (minutes of moderate and vigorous physical activity r = 0.59, p = 0.02; vigorous physical activity r = 0.63, p = 0.01). The reported proportion of children participating in moderate and vigorous physical activity was correlated with observations (r = 0.48, p = 0.03), as were reports of computer (r = 0.85) and TV/movie (r = 0.68) time compared to direct observations (both p < 0.01). CONCLUSIONS: OSNAP-OPAT can assist researchers and practitioners in validly assessing nutrition and physical activity environments and behaviors in afterschool settings. TRIAL REGISTRATION: Phase 1 of this measure validation was conducted during a study registered at clinicaltrials.gov NCT01396473.

Improving nutrition and physical activity policies in afterschool programs: results from a group-randomized controlled trial.

OBJECTIVE: Afterschool programs can be health-promoting environments for children. Written policies positively influence nutrition and physical activity (PA) environments, but effective strategies for building staff capacity to write such policies have not been evaluated. This study measures the comprehensiveness of written nutrition, PA, and screen time policies in afterschool programs and assesses impact of the Out of School Nutrition and Physical Activity (OSNAP) intervention on key policies. METHODS: Twenty afterschool programs in Boston, MA participated in a group-randomized, controlled trial from September 2010 to June 2011. Intervention program staff attended learning collaboratives focused on practice and policy change. The Out-of-School Time (OST) Policy Assessment Index evaluated written policies. Inter-rater reliability and construct validity of the measure and impact of the intervention on written policies were assessed. RESULTS: The measure demonstrated moderate to excellent inter-rater reliability (Spearman's r=0.53 to 0.97) and construct validity. OSNAP was associated with significant increases in standards-based policy statements surrounding snacks (+2.6, p=0.003), beverages (+2.3, p=0.008), screen time (+0.8, p=0.046), family communication (+2.2, p=0.002), and a summary index of OSNAP goals (+3.3, p=0.02). CONCLUSIONS: OSNAP demonstrated success in building staff capacity to write health-promoting policy statements. Future research should focus on determining policy change impact on practices.

School-day and overall physical activity among youth.

BACKGROUND: Increasing school-day physical activity through policy and programs is commonly suggested to prevent obesity and improve overall child health. However, strategies that focus on school-day physical activity may not increase total physical activity if youth compensate by reducing physical activity outside of school. PURPOSE: Objectively measured, nationally representative physical activity data were used to test the hypothesis that higher school-day physical activity is associated with higher overall daily physical activity in youth. METHODS: Accelerometer data from 2003-2004/2005-2006 National Health and Nutrition Examination Surveys were analyzed in 2012 to estimate physical activity levels during the school day (8AM-3PM) among youth aged 6-19 years (n=2548). Fixed-effects regressions were used to estimate the impact of changes in school-day minutes of moderate-to-vigorous physical activity (MVPA) on changes in total daily MVPA. RESULTS: Each additional minute of school-day MVPA was associated with an additional 1.14 minutes (95% CI=1.04, 1.24; p<0.001) of total daily MVPA, or 0.14 additional minutes (95% CI=0.04, 0.24; p=0.008) outside the school day, controlling for total daily accelerometer wear time and age, gender, race/ethnicity, and other non-time varying covariates. There were no differences in the effect of school-day MVPA on total MVPA by age group, gender, race/ethnicity, poverty status, or degree of change in MVPA. CONCLUSIONS: Higher school-day MVPA was associated with higher daily MVPA among U.S. youth with no evidence for same-day "compensation." Increasing school-based physical activity is a promising approach that can improve total daily physical activity levels of youth.

Racial/ethnic and gender differences in the association between self-reported experiences of racial/ethnic discrimination and inflammation in the CARDIA cohort of 4 US communities.

Inflammation is etiologically implicated in cardiometabolic diseases for which there are known racial/ethnic disparities. Prior studies suggest there may be an association between self-reported experiences of racial/ethnic discrimination and inflammation, particularly C-reactive protein (CRP). It is not known whether that association is influenced by race/ethnicity and gender. In separate hierarchical linear models with time-varying covariates, we examined that association among 901 Black women, 614 Black men, 958 White women, and 863 White men in the Coronary Artery Risk Development in Young Adults (CARDIA) study in four US communities. Self-reported experiences of racial/ethnic discrimination were ascertained in 1992-93 and 2000-01. Inflammation was measured as log-transformed CRP in those years and 2005-06. All analyses were adjusted for blood pressure, plasma total cholesterol, triglycerides, homeostatic model assessment for insulin resistance (HOMA-IR), age, education, and community. Our findings extend prior research by suggesting that, broadly speaking, self-reported experiences of racial/ethnic discrimination are associated with inflammation; however, this association is complex and varies for Black and White women and men. Black women reporting 1 or 2 experiences of discrimination had higher levels of CRP compared to Black women reporting no experiences of discrimination (ß = 0.141, SE = 0.062, P < 0.05). This association was not statistically significant among Black women reporting 3 or more experiences of discrimination and not independent of modifiable risks (smoking and obesity) in the final model. White women reporting 3 or more experiences of discrimination had significantly higher levels of CRP compared to White women reporting no experiences of discrimination independent of modifiable risks in the final model (ß = 0.300, SE = 0.113, P < 0.01). The association between self-reported experiences of racial/ethnic discrimination and CRP was not statistically significant among Black and White men reporting 1 or 2 experiences of discrimination. Further research in other populations is needed.

Associations of obesogenic behaviors in mothers and obese children participating in a randomized trial.

Relatively little research has assessed the association between obesogenic behaviors in parents and their children. The objective of the present analysis was to examine cross-sectional associations in television (TV)/video viewing, sugar-sweetened beverage intake, and fast food intake between mothers and their preschool aged children. We studied baseline data among 428 participants in High Five for Kids, a randomized controlled trial of behavior change among overweight and obese children of ages 2-6.9 years. The main exposures were whether mothers viewed TV/videos <1 h/day, drank <1 serving/day of sugar-sweetened beverages, and ate fast food <1 time/week. The main outcomes were whether children met these goals for the same behaviors. Using multivariate logistic regression adjusted for maternal and child characteristics, we estimated odds ratios of children meeting the behavioral goals. The majority of mothers ate fast food <1 time/week (73%) and drank <1 serving/day of sugar-sweetened beverages (73%), while few mothers viewed <1 h/day of TV/videos (31%). Most children met the fast food goal (68%), but not the goals for sugar-sweetened beverages (31%) or TV/video viewing (13%). In adjusted models, the odds ratios for a child meeting the goal were 3.2 (95% confidence interval (CI) 1.7, 6.2) for TV/video viewing, 5.8 (95% CI 2.8, 12.0) for sugar-sweetened beverage intake, and 17.5 (95% CI 9.8, 31.2) for fast food intake if their mothers met the goal for the same behavior. Obesogenic behaviors of mothers and preschool aged children were strongly associated. Our findings lend support to obesity prevention strategies that target parental behavior and the family environment.

Effect of an after-school intervention on increases in children's physical activity.

PURPOSE: Evaluate the effect of an after-school intervention on physical activity program changes and individual behaviors among children. METHODS: A quasi-experimental evaluation of a YMCA-driven environmental change intervention with 16 intervention and 16 control sites in four metropolitan areas in the United States. Intervention sites participated in learning collaboratives designed to promote physical activity and nutrition through environmental change, educational activities, and parent engagement. Behavioral foci included increasing overall physical activity levels as well as combined moderate and vigorous physical activity and vigorous physical activity. Outcomes were assessed longitudinally using preintervention and follow-up surveys of program implementation and accelerometer measures of physical activity. ActiGraph accelerometer data were collected from a sample of 212 children, ages 5-11 yr, attending the programs. On average, 3 d of data were gathered per child. Reliability of the accelerometer counts averaged 0.78. Multivariate regression models were used to control for potential confounding variables and to account for clustering of observations. RESULTS: Data indicate greater physical activity increases in children in intervention versus control sites after modest intervention implementation. Controlling for baseline covariates, children in intervention sites showed greater increases in average physical activity level than in control sites (76 counts per minute, P = 0.037, 95% confidence interval (CI) = 8.1-144) and more minutes of moderate and vigorous physical activity (10.5 min·d(-1), P = 0.017, 95% CI = 1.5-18.6), minutes of moderate physical activity (5.6 min·d(-1), P = 0.020, 95% CI = 0.99-10.2), and minutes of vigorous physical activity (5.1 min·d(-1), P = 0.051, 95% CI = 0.21-9.93). CONCLUSIONS: Results indicate significant increases in daily physical activity among children in intervention versus control sites. This study documents the effectiveness of an environmental change approach in an applied setting.

Disparities in youth physical activity in the United States: 2003-2006.

PURPOSE: This study aimed to examine changes in physical activity among children and adolescents, by race/ethnicity, in the United States from 2003-2004 to 2005-2006. METHODS: Secondary analysis of the objectively measured accelerometer data among children and adolescents 6-19 yr: 2003-2004 (n = 1665) and 2005-2006 (n = 1716) from the nationally representative National Health and Nutrition Examination Survey 2003-2004 and 2005-2006. We estimated regression coefficients for change between the two periods by age group, accounting for sampling design and adjusting for age, sex, race/ethnicity, and number of hours monitored. We tested for differences in mean accelerometer counts per minute and minutes per day of moderate and vigorous physical activity trends by race/ethnicity and gender. RESULTS: Physical activity decreased with age, boys were more active than girls, and non-Hispanic black children were more active than non-Hispanic whites (all P < 0.01). Overall mean accelerometer counts increased from 2003-2004 to 2005-2006 for children ages 6-11 yr (+31.6 counts per minute; 95% confidence interval = 0.51-62.6) but not among adolescents ages 12-19 yr. There was an increase over time in mean accelerometer counts among 6- to 11-yr-old non-Hispanic white children (+52.4 counts per minute, P = 0.007; 95% confidence interval = 15.7-89) but a decrease among non-Hispanic black and Mexican American children. No changes over the period in moderate and vigorous physical activity were found in either age group. CONCLUSIONS: The lack of improvement in physical activity among all children and adolescents and a potentially emerging race-ethnic disparity indicate a need for further research on potential mechanisms underlying these differences. Effective interventions to improve physical activity opportunities and attenuate the decline in activity levels as children enter adolescence are needed.

The global obesity pandemic: shaped by global drivers and local environments.

The simultaneous increases in obesity in almost all countries seem to be driven mainly by changes in the global food system, which is producing more processed, affordable, and effectively marketed food than ever before. This passive overconsumption of energy leading to obesity is a predictable outcome of market economies predicated on consumption-based growth. The global food system drivers interact with local environmental factors to create a wide variation in obesity prevalence between populations. Within populations, the interactions between environmental and individual factors, including genetic makeup, explain variability in body size between individuals. However, even with this individual variation, the epidemic has predictable patterns in subpopulations. In low-income countries, obesity mostly affects middle-aged adults (especially women) from wealthy, urban environments; whereas in high-income countries it affects both sexes and all ages, but is disproportionately greater in disadvantaged groups. Unlike other major causes of preventable death and disability, such as tobacco use, injuries, and infectious diseases, there are no exemplar populations in which the obesity epidemic has been reversed by public health measures. This absence increases the urgency for evidence-creating policy action, with a priority on reduction of the supply-side drivers.

Health and economic burden of the projected obesity trends in the USA and the UK.

Rising prevalence of obesity is a worldwide health concern because excess weight gain within populations forecasts an increased burden from several diseases, most notably cardiovascular diseases, diabetes, and cancers. In this report, we used a simulation model to project the probable health and economic consequences in the next two decades from a continued rise in obesity in two ageing populations--the USA and the UK. These trends project 65 million more obese adults in the USA and 11 million more obese adults in the UK by 2030, consequently accruing an additional 6-8·5 million cases of diabetes, 5·7-7·3 million cases of heart disease and stroke, 492,000-669,000 additional cases of cancer, and 26-55 million quality-adjusted life years forgone for USA and UK combined. The combined medical costs associated with treatment of these preventable diseases are estimated to increase by $48-66 billion/year in the USA and by £1·9-2 billion/year in the UK by 2030. Hence, effective policies to promote healthier weight also have economic benefits.