intervention is often delivered in clinical settings. However, there are several important differences between prevention and treatment approaches (Kumanyika and Obarzanek, 2003). The targeted outcomes are different: prevention of weight gain is a satisfactory outcome for prevention approaches, whereas weight loss is the desired outcome for treatment. Motivations to maintain a healthful rate of weight gain for growing children may differ in nature and intensity from motivations to lose weight. Although treatment approaches may include relatively extreme behavioral changes over the short term, preventive strategies usually necessitate long-term continuation.
The committee’s approach to obesity prevention is similar to the range of prevention efforts that have been used to address many other public health problems. Some efforts directly change the physical environment but require no purposeful action on the part of the target population (e.g., fluoridation of community drinking water and food fortification); others directly require behavior change in targeted high-risk populations (e.g., immunization of children); and some require environmental change to facilitate behavioral change (e.g., zoning and land-use regulations to encourage physical activity). The majority of efforts require multiple approaches; for example, efforts to reduce underage drinking and tobacco control have involved legislation, media campaigns, counseling, and many other mechanisms (NRC and IOM, 2003; Mensah et al., 2004).
Appendix B provides a glossary of terms used throughout this report.
Using an ecological perspective, the committee developed a framework to depict the behavioral settings and leverage points that influence both sides of the energy balance2 equation—energy intake and energy expenditure. An ecological systems theory model postulates that changes in individual characteristics are affected not only by personal factors (e.g., age, gender, genetic profile) but also by interactions with the larger social, cultural, and environmental contexts in which they live (e.g., family, school, community) (Figure 3-1) (Davison and Birch, 2001; Lobstein et al., 2004).
Building on this ecological model and drawing upon concepts from several relevant frameworks (Swinburn et al., 1999; Booth et al., 2001; Kumanyika et al., 2002; Swinburn and Egger, 2004), the committee developed a framework that shows layers of ecologic factors as influences on energy imbalance, which is shown as the typical graphic in which energy