10
Research and Policy Recommendations

There is an epidemic of obesity in the United States among both adults and children that shows no signs of abating. In Chapter 2, we estimate the economic costs of obesity to exceed $100 billion per year, counting the costs of illness resulting from this disease and the money spent on weight-reduction products and services. Given that obesity is one of the most important public health problems, it is perhaps both surprising and unfortunate that the causes of obesity and its management remain poorly understood and that research into preventing and treating it has not yielded more promising results. The National Institutes of Health (NIH) spent approximately $35 million in fiscal year 1992 on direct research in obesity, representing about 10 percent of total NIH obligations in biomedical nutrition research and training that year, or 0.4 percent of total NIH research and training expenditures (NIH, 1994). Given the magnitude of the problem of obesity in this country, we agree with a recent recommendation of the National Task Force on Prevention and Treatment of Obesity of NIH to double the current NIH expenditures on direct obesity research in real dollars over the next five years (NTF, 1994a).

Several publications have provided well-considered recommendations for further research to better understand, prevent, and treat obesity. These include The Surgeon General's Report on Nutrition and Health (DHHS, 1988), the National Academy of Sciences report Diet and Health (NRC, 1989a), and Opportunities in the Nutrition and Food Sciences by the Institute of Medicine (IOM, 1993). Most recently, the National Task Force on Prevention



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Weighing the Options: Criteria for Evaluating Weight-Management Programs 10 Research and Policy Recommendations There is an epidemic of obesity in the United States among both adults and children that shows no signs of abating. In Chapter 2, we estimate the economic costs of obesity to exceed $100 billion per year, counting the costs of illness resulting from this disease and the money spent on weight-reduction products and services. Given that obesity is one of the most important public health problems, it is perhaps both surprising and unfortunate that the causes of obesity and its management remain poorly understood and that research into preventing and treating it has not yielded more promising results. The National Institutes of Health (NIH) spent approximately $35 million in fiscal year 1992 on direct research in obesity, representing about 10 percent of total NIH obligations in biomedical nutrition research and training that year, or 0.4 percent of total NIH research and training expenditures (NIH, 1994). Given the magnitude of the problem of obesity in this country, we agree with a recent recommendation of the National Task Force on Prevention and Treatment of Obesity of NIH to double the current NIH expenditures on direct obesity research in real dollars over the next five years (NTF, 1994a). Several publications have provided well-considered recommendations for further research to better understand, prevent, and treat obesity. These include The Surgeon General's Report on Nutrition and Health (DHHS, 1988), the National Academy of Sciences report Diet and Health (NRC, 1989a), and Opportunities in the Nutrition and Food Sciences by the Institute of Medicine (IOM, 1993). Most recently, the National Task Force on Prevention

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Weighing the Options: Criteria for Evaluating Weight-Management Programs and Treatment of Obesity of NIH has published a comprehensive report on research needs in obesity (NTF, 1994a). The report presents research recommendations in the following areas: genetic and environmental determinants of obesity, the role of obesity in the pathogenesis of chronic diseases, treatment of obesity, prevention of obesity, and communicating research findings to the lay public and health-care providers. The interested reader should refer to these publications, which, taken together, set forth a comprehensive set of needs in obesity research. The research and policy recommendations discussed below are focused more directly on the contents of this report. CAUSES OF OBESITY AND ASSOCIATED COMORBIDITIES One of the more perplexing aspects of obesity treatment is why the vast majority of individuals are largely unsuccessful at long-term management of their weight. We believe that it is because the symptoms of obesity are treated rather than its fundamental causes. It is clear that obesity in many individuals involves an interaction between genes and the environment. Until the fundamental causes of this disease with multiple etiologies are understood—its pathophysiology and development at the genetic, molecular, and cellular levels and its interactions with relevant environmental factors—obesity will be extremely difficult to prevent and cure. An analogy that may prove helpful is that of the evolution of therapy for cystic fibrosis (CF). The treatment of this debilitating disease has traditionally focused on relieving the symptoms (i.e., the pulmonary infections), improving bronchial draining, and improving nutrition. Though conventional treatments have improved incrementally over time, they provide only short-term improvements in the quality and quantity of life, and more than 90 percent of individuals with CF die at an average age of 29 years (Fuchs et al., 1994). Recent genetic and molecular studies on CF have uncovered the structural defects that lead to pathogenesis. For example, it was discovered that the accumulation of secretions that block the airways is a result of the release of extra cellular DNA by leukocytes. In addition, advances in molecular genetics have led to an understanding of the fundamental genetic defect in CF to the extent that gene-replacement therapy is being studied (Zabner et al., 1993). One of the clinical benefits to date of this research into the molecular and genetic underpinnings of CF has been the development of aerosolized recombinant human DNAse, which is now used to make the secretions easier to expectorate (Davis, 1994; Fuchs et al., 1994). Using the exciting tools of biotechnology to prevent or cure obesity is

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Weighing the Options: Criteria for Evaluating Weight-Management Programs undoubtedly distant. However, some tools already exist that can be applied to understanding the causes, pathophysiology, and development of obesity at the genetic, molecular, and cellular levels. Research approaches to identify and assess the multigenic components of obesity include the use of animal models and, in humans, studying twins and families. Further characterization of the human genome should aid in identification of the genetic components of human obesity, particularly as variable phenotypic expressions of obesity are better delineated. Special emphasis should be placed on obtaining a fundamental understanding of the events that contribute to the development of comorbidities. This understanding can ultimately be applied to the development of more effective treatment strategies, including more effective drugs designed to modify specific defects. Much also remains to be learned about the behavioral and environmental influences on the expression of obesity. The fact that genetic and environmental determinants of obesity vary among population groups makes this variation and the reasons for it important areas of research. TREATMENT OF OBESITY AND MAINTENANCE OF WEIGHT LOSS There is general agreement that the basic elements of obesity treatment should include self-monitoring, goal setting, exercise, nutrition education, stress management, and social support. However, there is a great need for research in these areas. Among them, though not listed in any priority order, are the following: Determine the physiological, biochemical, molecular, and behavioral mechanisms by which antiobesity drugs and gastric surgery promote long-term weight loss. Determine whether a gradual fat-reduction method is more effective than restrictive dieting for long-term weight maintenance and improvement in health. Uncover the physiological and psychological mechanisms responsible for loss and regain of eating control (e.g., avoidance of excessive restrictions and binges) with various eating patterns. Show how counselors may be more successful at persuading and empowering those individuals focused on becoming thin to set realistic goal weights for themselves and become more focused on improving their dietary patterns and level of fitness. Identify the period of attendance required to produce group cohesion and effective peer-support networks. Because longer treatments have produced greater weight losses, there is a need to discover optimal

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Weighing the Options: Criteria for Evaluating Weight-Management Programs treatment length and methods, while taking cost effectiveness into account. Determine factors that can predict an individual's success with different types of diet and activity interventions. Identify program components that constitute successful weight maintenance through diet and activity without inducing undesirable consequences (e.g., harm to psychological well-being and overcompensation). Explore the use of self-help groups to enhance and maintain long-term healthy eating and exercise behaviors. Understand the development or etiological significance of eating disorders in obese individuals. Define the determinants of physical activity and healthy dietary patterns and how to initiate and maintain them in various population subgroups. Determine the effects of various environmental and situational factors on food selection and the initiation of physical activity. Are individuals who exercise more or less likely to be sedentary the rest of the day? Understand temporal trends in natural weight changes and develop strategies for individuals to identify, desire, achieve, and maintain healthy weights. Describe the long-term effects of various eating patterns (e.g., meals versus snacks and night eating) as they might affect the development of obesity. Determine how nutrients and activity patterns may affect genetic potential in regard to fat distribution patterns, eating habits, and food cravings. Elucidate the roles of diet and activity in the prevention of weight gain. Investigate the relative importance of how one loses weight (e.g., through diet or a combination of methods) to the risk of obesity-related diseases. Study whether rate of weight loss affects one's ability to keep weight off in the long run and whether it is easier to maintain lower or higher levels of weight loss. Investigate how individuals make decisions about which weight-loss method or program to select and which to reject. PREVENTION OF OBESITY The prevention of obesity should be given a high priority in any rational system of health care. However, given the very limited success

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Weighing the Options: Criteria for Evaluating Weight-Management Programs of efforts at prevention, the pressing need is for more research. We consider the prevention of obesity from the point of view of (1) preventing obesity from occurring, (2) preventing weight gain following weight reduction, and (3) preventing further weight gain among obese persons who cannot lose weight. Of these three, a large amount of research has been devoted to item 2 with, as yet, disappointing results. This research has been conducted within the framework of treatment. It will undoubtedly continue within this framework and thus is less relevant in terms of prevention than the other two items. Preventing obesity from occurring is, of course, highly desirable and often the object of enthusiastic advocacy. It is therefore important to keep in mind the disappointing results of universal prevention as shown in the carefully conducted community risk-factor-reduction trials (see Chapter 9). It may be that more tightly focused programs of prevention will be more effective. Such programs might reasonably be focused on a particular stage in life (e.g., childhood, adolescence, early middle age, or pregnancy), on particular locations (e.g., school, work site, or community center), or on special circumstances (e.g., smoking cessation or pregnancy). The prevention of further weight gain in persons who cannot lose weight is an area that has been largely neglected in the past and one that could conceivably yield substantial health benefits. Additional research needs in the area of obesity prevention are as follows: Studies are needed to assess the usefulness of medication(s), including combinations of drugs, in the prevention of both further weight gain and regain of weight following treatment. Recent studies of long-term use of medication, refuting the belief that tolerance develops to its effects, clear the way for more aggressive use of this therapy. Studies should be designed to assess the applicability of a ''harm-reduction" approach to prevention. Developed originally as an approach to substance abuse prevention and treatment (Marlatt and Tapert, 1993; Marlatt et al., 1993), harm reduction is based on a continuum model, with incremental changes encouraged (e.g., encouragement of proximal goals of gradual weight loss over time in contrast to traditional programs with their emphasis on distal goals of ideal weight loss). The harm-reduction model is consistent with a stepped-care approach that begins with the least intensive intervention before proceeding to more intensive and expensive steps. Studies are needed that compare the impact of prevention programs designed for specific weight-loss goals with others designed to (1) affect personal beliefs in ideal body image, (2) decrease reliance on exaggerated  

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Weighing the Options: Criteria for Evaluating Weight-Management Programs dietary behaviors, and (3) treat associated eating disorders (e.g., binge and purge cycling). Studies should be conducted to investigate the effects of prevention programs representing either (1) individual clinic-based intervention programs designed to modify personal behavior; (2) community-based public health programs, including public policy and regulatory policy change; or (3) a combination of both clinical and public health approaches. Research on unaided weight management is necessary, for example, natural-history studies of formerly obese people who learned to manage their weight successfully by themselves and investigations of people who are at risk for obesity but who nonetheless maintain healthy weights. We recommend that, where possible, such long-term studies be included as part of ongoing long-term clinical and observational trials (e.g., the NIH Women's Health Initiative). POLICY RECOMMENDATIONS While we are optimistic that research will eventually uncover the causes of obesity and lead to better management, prevention, and treatment of this disease, the application of scientific findings alone is rarely enough to resolve public health problems. Public policies are needed to translate the research findings into usable information for the public and health-care providers and to create an environment that encourages the attainment and maintenance of healthy weight, healthful dietary patterns, and regular physical activity. As described throughout this report, obesity is a major public health problem and is arguably the main nutritional and metabolic disease in this country. However, scientists are quite ignorant about the causes of obesity as well as its prevention and treatment. Therefore, it is best that priority be given to research to understand its causes, rather than spending substantial amounts of money on major new large-scale efforts to prevent and treat this disease given the inadequate tools we have at present. Our first policy recommendation is that there be a change in thinking in this country by the public and health-care providers alike to treat obesity as an important chronic, degenerative disease that debilitates individuals and kills prematurely. Obesity is a disease that has fundamental genetic and cellular components as well as social and behavioral components. Recognizing obesity as one of this country's most important nutrition-related diseases has important consequences for the funding of research by government, foundations, and private agencies; for health-care

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Weighing the Options: Criteria for Evaluating Weight-Management Programs reform; and for oversight of the weight-loss industry by regulatory agencies. Our second policy recommendation concerns the need for increased recognition and support for research in genetics and molecular and cellular biology to aid in understanding the causes of obesity and its associated comorbidities. Research in these areas should be greatly expanded to take advantage of the new knowledge and techniques in molecular genetics and cell physiology that are contributing to substantial advances in the treatment of numerous other diseases. Expanding and coordinating this important research effort will require a greater organizational emphasis both within NIH itself and in other agencies. Developing a research work force that can make the necessary discoveries and applications is going to require careful reevaluation of current training patterns and enhancement of training with a very strong interdisciplinary flavor. Research into the causes and, ultimately, the prevention of obesity requires people trained in the basic sciences as well as dietetics and the social sciences. Our third policy recommendation is that there be developed a more aggressive policy of informing the public and health-care providers about the nature of obesity, the difficulties inherent in treating this disease, and the need for susceptible individuals to take steps to prevent its occurrence or minimize its development. The techniques to be utilized are those suggested for informing the public of methods to be used in the evaluation of obesity treatment (Chapter 8). Health-care providers could be encouraged to discuss obesity with their obese clients and with those who are beginning to gain excess weight. What is needed are simple messages and communications between the provider and the person at the very early stages of weight gain as well as when the person is obese. Other important policy recommendations include the following: One set of definitions and standards should be developed for defining and measuring obesity. The current variation in terminology used to describe excess weight leads to difficulties in identifying precisely the extent of obesity and in trying to compare the results of different studies. Not only are terms such as overweight and obesity used interchangeably, there is considerable disagreement concerning how to identify those at increased risk from excess weight. Disagreement also exists about the body mass index (BMI) cutoff between a "healthy" and an "unhealthy" weight. To enable more individuals who would like to lose weight to take advantage of the many programs that currently exist, study is needed on payment models and how cost affects the entry of people into programs, their participation in them, and the long-term outcomes for the participants.  

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Weighing the Options: Criteria for Evaluating Weight-Management Programs As this country debates health-care reform, attention should be paid to reimbursement mechanisms for nutrition services generally and for obesity treatment programs—certainly the clinical programs and some of the appropriate nonclinical programs as well. Initiatives should be developed that will motivate more people to become physically active. While physical activity enhances health and helps to prevent and treat obesity, people must believe they can fit it into their lives and think of it as an enjoyable way to spend time before they will make the effort. To encourage activity, communities should consider developing innovative social-marketing campaigns, more safe and well-lighted walking and bicycle paths and playgrounds, and low- or no-cost recreation centers supporting a variety of activities. At the national level, the U.S. Public Health Service should continue to expand its efforts to become a more visible advocate of the pleasures and health benefits of an active lifestyle, particularly to children, adolescents, the elderly, and those in lower socioeconomic groups. Investigations should be conducted to determine what methods are most likely to be productive in increasing physician training in the management of obesity. The potential impacts of modifying health insurance reimbursement systems on the treatment and long-term management of obesity should be examined. CONCLUDING REMARKS The epidemic of obesity in the United States is increasing at a cost to this country of more than $100 billion per year, yet research to understand the causes of this disease and how to more effectively prevent and treat it is seriously underfunded. This chapter has identified some important research needs that offer the hope of substantially reducing the prevalence of this important public health problem, thereby decreasing health-care costs and improving the overall health of the U.S. population. We urge NIH in particular to increase its funding of investigator-initiated research to answer fundamental questions, such as those presented in this chapter, pertaining to the treatment and prevention of obesity.