Bridging the Evidence Gap in Obesity Prevention A Framework to Inform Decision Making (2010) / Chapter Skim
Currently Skimming:
1 Introduction
1 Introduction
Pages 17-34
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 17... ...
• There is a pressing need to act on the problem of obesity, but there is also a large gap between the types and amount of evidence deemed ideal as the basis for taking action and the types and amount of information available to meet that need. • The Committee on an Evidence Framework for Obesity Prevention Decision Making was formed to address the issues of how to identify, use, and evaluate evidence to inform obesity prevention decisions and how to generate evidence where it is lacking.
|
From page 18... ...
But the increasing preva lence of obesity in diverse populations reveals the limitations of biological controls on energy balance in the face of high caloric availability and diminished caloric expen diture through routine physical activity. Nor does the recognition of environmental influences on obesity negate the importance of individual weight control efforts; how ever, the level of effort required makes individuals' attempts to control their weight notoriously ineffective over the long term.
|
From page 19... ...
STUDY CHARGE, APPROACH, AND SCOPE Several prior IOM committees have faced the need to work around evidence gaps and the fact that evidence hierarchies applied to medical treatment have limita tions for assessing population-based preventive interventions. A committee tasked to develop a national action plan for child obesity prevention ultimately developed a set of principles to guide its process for reviewing evidence and making recommenda tions.
|
From page 20... ...
The committee members were selected to include academic researchers, practi tioners, and policy makers, representing content expertise in various aspects of child and adult obesity prevention interventions; public health policy practice and research more generally; and research methodology from the perspectives of biomedicine, edu cation, and psychology. The committee was tasked to: • provide an overview of the nature of the evidence base for obesity prevention as it is currently construed; • identify the challenges associated with integrating scientific evidence with broad er influences on policy and programmatic considerations; • provide a practical and action-oriented framework of recommendations for how to select, implement, and evaluate obesity prevention efforts; • identify ways in which existing or new tools and methods can be used to build a useful and timely evidence base appropriate to the challenges presented by the obesity epidemic, and describe ongoing attempts to meet these challenges; Bridging the Evidence Gap in Obesity Prevention 0
|
From page 21... ...
Given a dearth of information to address an urgent public health problem, the infor mation that is available will be valued differently and efforts to fill evidence gaps given high priority. Study Scope This study was designed to go beyond obesity prevention as such, also yielding guid ance for more general efforts to address complex, multifactorial public health chal lenges and examining the application of a systems perspective to the contexts in which policy and programmatic decisions that address such challenges are made.
|
From page 22... ...
OBESITY AS A SOCIETYWIDE PROBLEM Overweight and obesity -- reflecting a gain of excess body fat -- result from the cumula tive and initially imperceptible effects of hour-to-hour and day-to-day eating and phys ical activity behaviors that create a surplus of calories consumed relative to calories expended. Excess weight gain is usually unintentional and gradual, and it is difficult to reverse on a permanent basis.
|
From page 23... ...
, it is important to know whether one of these two factors is the primary driver of the obesity epidemic in order to prioritize potential interventions. The relative contributions of increased energy intake and decreased energy expenditure to the obesity epidemic have been debated, with some suggesting that increased energy intake is sufficient to explain the weight gain of the American population since the 1970s (Bleich et al., 2008; Swinburn et al., 2009)
|
From page 24... ...
The same could be true for non Hispanic white women, with even higher levels for non-Hispanic black and Mexican American women, for whom the prevalence of obesity was already greater than 50 percent and 40 percent, respectively. Prevention efforts should not only aim to improve weight levels in the popula tion at large but also target subpopulations with higher-than-average risk.
|
From page 25... ...
1999 -2004 2020 2030 Boys ages 6 to 11 Girls ages 6 to 11 50 41.1 39.5 40 Percent Obese 30.2 27.7 26.5 26.5 30 25.3 25.1 19.4 18.5 16.9 17.5 20 10 0 Non- Non- Mexican Non- Non- Mexican Hispanic Hispanic American Hispanic Hispanic American white black white black FIGURE 1-3 Projected increases in childhood obesity (defined as BMI ≥ 95th percentile based on CDC growth charts) if current trends continue, for males and females in three U.S.
|
From page 26... ...
However, real-life experience demonstrates that policy or programmatic decision making is not always such a linear process and that initiatives grounded in an idea generated by a research study may be the excep tion. Formal evidence may be used in highly variable ways, at different stages of a Bridging the Evidence Gap in Obesity Prevention 26
|
From page 27... ...
Additionally, making decisions about prevention is inherently complex, especially for problems, such as obesity, with multiple types and layers of causation. Moreover, prevention (keeping something TABLE 1-2 Physical, Social, and Emotional Health Consequences of Obesity in Adults, Children, and Youth Physical Health Social Health Emotional Health • Cardiovascular disease • Stigma • Low self-esteem • Cancer • Negative stereotyping • Negative body image • Glucose intolerance and insulin resistance • Discrimination • Depression • Type 2 diabetes • Teasing and bullying • Hypertension • Social marginalization • Dyslipidemia • Hepatic steatosis • Cholelithiasis • Sleep apnea • Menstrual abnormalities • Impaired balance • Orthopedic problems SOURCES: IOM, 2005; WHO, 2000.
|
From page 28... ...
Actions within many of these levels are focal points for dis cussion on how to combat the obesity epidemic within the United States and glob ally. Pathways or logic models can be drawn to link these levels to weight-related behaviors of population groups and individuals, such as food purchases; intakes of sugar-sweetened beverages, fruits and vegetables, whole grains, and total calories; tele vision watching and other screen time; automobile use; breastfeeding; and routine and recreational physical activity.
|
From page 29... ...
, food prices, agricultural policies and food production systems, community design aspects that influence outdoor activity, building design aspects that influence indoor activity, public transportation, insurance coverage for wellness services, poverty levels, funding lev els for and regulations guiding federal nutrition assistance programs, and school and worksite environments related to food and physical activity (IOM, 2009; James et al., 2006; WHO, 2004; World Cancer Research Fund and American Institute for Cancer Research, 2009)
|
From page 30... ...
Those shown in italics are decisions likely to be made based on priorities unrelated to obesity but with potential effects on eating or physical activity. The decision scenarios in Box 1-1 all relate in some way to decisions about interven tions; these types of questions are central to obesity prevention.
|
From page 31... ...
on physical activity or • A city planning authority is considering closing city center streets to automobile use to weight-related behavior reduce traffic flow and increase pedestrian access to local businesses. of adults or children • A federal authority is attempting to determine whether there are sufficient grounds to implement statutory restrictions on television and Internet advertisements directed at children.
|
From page 32... ...
Chapter 10 summarizes the commit tee's conclusions and presents recommendations for supporting the identifica tion, use, and evaluation of evidence to inform obesity prevention decisions and generate evidence when it is lacking. For reference throughout the report, a list of acronyms and glossary of terms is provided in Appendix A; a table listing current efforts to improve research and practice in the field of obesity prevention or public health is given in Appendix B; Appendix C contains a table listing current reviews of obesity prevention interven tions and strategies; Appendix D provides a list of selected information sources for locating evidence; Appendix E presents an in-depth discussion of some study design alternatives to randomized controlled trials and how theory, professional experience, and local wisdom can be used when evidence is lacking; Appendix F contains the agenda of two public workshops held by the committee; and Appendix G presents biographical sketches of the committee members.
|
From page 33... ...
2009. Local government actions to prevent childhood obesity.
|
From page 34... ...
Food, nutrition, and physical activity: A global perspective. Washington, DC: American Institute for Cancer Research.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.