The prevalence of overweight and obesity2 is high among children and adults in the United States and particularly so for some demographic groups, with serious health, economic, and social consequences. Carrying excess weight raises an individual’s risk of health problems that include cardiovascular disease, gallbladder disease, type 2 diabetes, hypertension, dyslipidemia, and osteoarthritis, while psychosocial consequences of overweight and obesity may impair functioning and quality of life (IOM, 2005). Health problems related to obesity are also expensive: by one estimate, the annual medical burden of obesity could reach $147 billion (Finkelstein et al., 2009). Additional costs to society come in the form of reduced productivity at and absenteeism from work and higher costs for disability and unemployment benefits, for example (Cawley et al., 2007; Finkelstein et al., 2005). The social costs of obesity can include stigmatization, discrimination, and teasing and bullying (IOM, 2005). In addition, national security is affected by rising rates of obesity. U.S. military leaders have recently
1This report summarizes the views expressed by workshop participants, and while the committee is responsible for the overall quality and accuracy of the report as a record of what transpired at the workshop, the views contained herein are not necessarily those of the committee.
2Researchers classify adults with a body mass index (BMI) of 25 to 29.9 as overweight, those with a BMI of 30 or higher as obese, and those with a BMI of 40 or higher as extremely obese. Children and adolescents with a BMI for age and sex at or above the 95th percentile or at or above the 85th but below the 95th percentile (based on the Centers for Disease Control and Prevention’s [CDC’s] growth charts) are classified as obese or overweight, respectively.
described the role of obesity in reducing the pool of potential recruits to the armed services (Christeson et al., 2010).
Rates of adult and childhood obesity in the United States vary significantly by region and by race/ethnicity and age, but overall rates are high. Data from the 2007-2008 National Health and Nutrition Examination Surveys (NHANES)3 show that among adults aged 20 or older, nearly 34 percent have weight levels in the obese range, and another 34 percent are classified as overweight; thus the combined prevalence of obesity and overweight is nearly 68 percent (Flegal et al., 2010). Among children and adolescents aged 2 through 19, nearly 17 percent are classified as obese and 15 percent as overweight; thus close to 32 percent are either obese or overweight (Ogden et al., 2010).
While there is no evidence that underlying biological susceptibility to weight gain has changed, there is ample evidence of increases in such factors as the amount of food available; the palatability of food (i.e., increases in fat, sugar, and salt); and eating environments that are highly conducive to the consumption, often unintentional, of excess calories (Gearhardt et al., 2011; Kral and Rolls, 2004; Ledikwe et al., 2005; Story et al., 2008; Wansink, 2004). As a result, researchers and policy makers are focusing increased attention on environmental and policy factors that may affect obesity. Individual factors, including genetics, psychological issues, and social and cultural factors, play a role in people’s diets, but so do the physical environments in which they live, the kinds of food that are accessible and affordable where they live and work, the marketing and other media messages they receive, and public policies such as requirements for sidewalks or provision of nutrition information in restaurants.
In this context, the Institute of Medicine (IOM) formed the Committee on Accelerating Progress in Obesity Prevention, which was charged to review IOM’s past obesity-related recommendations, identify a set of critical recommendations for future action, and recommend indicators of progress in implementing these actions. Given the urgency of a problem that has been described as an epidemic, researchers and policy makers are eager to identify improved measures of the behavioral influences that may contribute to obesity and of the effectiveness of policies designed to reduce obesity rates. Accordingly, as part of its information-gathering process, the committee conducted a workshop in March 2011 to explore measurement methodology in obesity prevention. Held with the support of the Michael & Susan Dell Foundation and the Robert Wood Johnson Foundation, the workshop was an opportunity for the committee to discuss opportunities and challenges related to measurement and to hear from experts in many
3NHANES is a continuous program of studies designed to assess the health and nutritional status of a nationally representative sample of children and adults in the United States.
relevant fields, including public health, epidemiology, nutrition, media studies and communication, psychology, and public policy. The workshop was designed to support the committee in carrying out its charge, and not to serve as a forum for the committee to discuss findings or conclusions related to the charge.
This report summarizes the presentations and discussions at the workshop. Chapters 2 and 3 provide an overview of issues related to measurement in two key areas: Chapter 2 addresses physical activity and the built environment, while Chapter 3 focuses on food and nutrition policies and environments. Chapter 4 reviews the measures, data sources, and methods that relate to both of these environments and may help researchers and policy makers assess progress in obesity prevention. Chapter 5 examines marketing strategies, public health campaigns, and data on marketing exposure. Chapter 6 focuses on state and local policy efforts, exploring both existing measures of their effectiveness and possibilities for the future. Chapter 7 addresses the ethnic, geographic, and other disparities in obesity prevalence that must be considered in measuring progress in obesity prevention. The final chapter presents a summary of key themes from the workshop.
Cawley, J., J. A. Rizzo, and K. Haas. 2007. Occupation-specific absenteeism costs associated with obesity and morbid obesity. Journal of Occupational and Environmental Medicine 49(12):1317-1324.
Christeson, W., A. D. Taggart, and S. Messner-Zidell. 2010. Too fat to fight: Retired military leaders want junk food out of America’s schools. Washington, DC: Mission: Readiness.
Finkelstein, E., I. C. Fiebelkorn, and G. Wang. 2005. The costs of obesity among full-time employees. American Journal of Health Promotion 20(1):45-51.
Finkelstein, E. A., J. G. Trogdon, J. W. Cohen, and W. Dietz. 2009. Annual medical spending attributable to obesity: Payer and service-specific estimates. Health Affairs 28(5): w822-w831.
Flegal, K. M., M. D. Carroll, C. L. Ogden, and L. R. Curtin. 2010. Prevalence and trends in obesity among U.S. adults, 1999-2008. Journal of the American Medical Association 303(3):235-241.
Gearhardt, A. N., C. M. Grilo, R. J. DiLeone, K. D. Brownell, and M. N. Potenza. 2011. Can food be addictive? Public health and policy implications. Addiction 106(7):1208-1212.
IOM (Institute of Medicine). 2005. Preventing childhood obesity: Health in the balance. Edited by J. P. Koplan, C. T. Liverman, and V. A. Kraak. Washington, DC: The National Academies Press.
Kral, T. V. E., and B. J. Rolls. 2004. Energy density and portion size: Their independent and combined effects on energy intake. Physiology and Behavior 82(1):131-138.
Ledikwe, J. H., J. A. Ello-Martin, and B. J. Rolls. 2005. Portion sizes and the obesity epidemic. Journal of Nutrition 135(4):905-909.
Ogden, C. L., M. D. Carroll, L. R. Curtin, M. M. Lamb, and K. M. Flegal. 2010. Prevalence of high body mass index in U.S. children and adolescents, 2007-2008. Journal of the American Medical Association 303(3):242-249.
Story, M., K. M. Kaphingst, R. Robinson-O’Brien, and K. Glanz. 2008. Creating healthy food and eating environments: Policy and environmental approaches. Annual Review of Public Health 29:253-272.
Wansink, B. 2004. Environmental factors that increase the food intake and consumption volume of unknowing consumers. Annual Review of Nutrition 24:455-479.