Division of Nutrition

6th Annual
Postgraduate Nutrition Symposium

Science-Based Solutions to Obesity:
What is the Role of Academia, Government, and Industry?

March 10 - 11, 2005

(Alphabetically by speaker)

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George L. Blackburn, M.D., Ph.D.
S. Daniel Abraham Associate Professor of Nutrition
Associate Director of Nutrition, Division of Nutrition
Harvard Medical School
Beth Israel Deaconess Medical Center
Center for the Study of Nutrition Medicine

Academia—Best Practices in Teaching and Research

We need to close the gap between what health professionals know, and what parents and children understand about physical activity and healthy eating. There’s abundant nutritional information available, but do parents know how to use it? Can they explain it to their children? According to U.S. Surgeon General Richard Carmona, many people, even educated Americans, don’t know what a calorie is, or how to burn it. Our job is to make that kind of information meaningful and helpful. Harvard’s new Academy is developing best practices in teaching to enhance learning and increase health literacy—the ability to access and use health-related information and services to make appropriate health decisions. Prior knowledge is key to learning. Links between new and prior knowledge lead to revised interpretations of meaning that guide future actions. Teaching how to read a single food label can start the process. The built environment contributes to obesity. Environmental health research and evidence-based interventions can help address this epidemic. To make healthy choices, parents and children need easy-to-understand information that fits into their busy lifestyles. Leaders in academia, government, and industry need to use best practices in teaching and research to make sure they get the information they need, and know how to use it.

The challenge we have is taking the scientific information to the consumer. Data shows that parents make sacrifices for their children and children’s health. Richard Carmona, MD, MPH, FACS, Surgeon General of the US, March 2, 2004, said, "Kids don’t automatically know how important it is to be active for one hour a day. They don’t know they need 5 to 9 servings of fruits and vegetables per day." Further, "Parents need to be good role models by being physically active and encouraging their children to exercise and make healthy choices about what they eat and how much they eat." To make healthy choices, parents and children need easy-to-understand information that fits into their busy lifestyles. There is a lot of information out there, but do parents really understand it? We need to close the gap between what health professionals know and what parents and children know about physical activity and healthy eating. We need to increase health literacy. Harvard’s new Academy can apply best teaching practices to enhance learning and to help parents and children make healthy food choices. Environment contributes to obesity. Environmental health research and evidence-based interventions can address this public health problem. Scientific leaders in government, academia and industry need to make sure that consumers have the information they need to make healthy choices about eating and physical activity.

Adam Drewnowski, Ph.D.
Professor, Epidemiology
Director, Nutritional Sciences Program
Director, Center for Public Health Nutrition
University of Washington

Public Health Approach to Obesity: Do healthier diets cost more?

Obesity rates in the US are increasing steadily for all ages, all races, and all income groups. Yet major social disparities persist and the burden of obesity and type 2 diabetes falls disproportionately on racial/ethnic minorities and the poor. It is the lower-income states -Mississippi, Alabama, Louisiana and West Virginia that have the highest obesity rates. The low-income Los Angeles County has the highest proportion of unfit and overweight children in California and higher rates of diabetes-related deaths relative to the more affluent districts. Obesity in the US is, to a large extent, an economic phenomenon. Many people are obese because they are poor. The causal association between poverty and obesity may be mediated through unequal access to nutritious and affordable diets. Energy-dense foods, some of them high in refined grains, added sugars and added fats, provide dietary energy at a far lower cost than do lean meats, fish, fresh vegetables and fruit. As long as this situation continues, noted a editorial in The Lancet, "the battle against obesity will be lost." People select foods based on taste, cost and convenience. Higher food costs are a barrier to the adoption of healthier diets, especially by low-income households. If healthier diets cost more, then dietary guidelines, based on a pyramid of relatively costly foods, may not be the best approach to population-based interventions in public health. People whose resources are limited may perceive them as elitist and cruel. There is a need for more studies on the relationship between socioeconomic factors, diet quality, and diet costs."

Gary Foster, Ph.D.
University of Pennsylvania

The Behavioral Management of Obesity

Making the obese patient comfortable in a healthcare office is important. Health care professionals should have gowns available to fit larger patients and a scale that can weigh all patients. Health care professionals should use larger blood pressure cuffs when appropriate and provide some armless chairs in the waiting room. The same behavioral treatments/changes will produce different results in different individuals. The number one thing is to get people to self-monitor by writing down what, when, where, and how much they eat. Using behavior modification and diet in addition to medication greatly increases initial weight loss. It is essential to congratulate patients on successes, even if small, and not to criticize them for short-comings. Make sure that a patient’s weight-loss goal is attainable. One study showed that a patient’s average weight loss goal was a 32% reduction in body weight. This is three times greater than the goals recommended by the National Academy of Science and US Department of
Agriculture and greatly exceeds weight losses for non-surgical treatments.
There are very good data to show that a 5-10% weight loss has metabolic benefits, yet a study showed that patients would be disappointed if they achieved a 17% weight loss. We need to convince the public that a 10% weight loss is a healthy outcome worth pursuing.

Daniel Glickman
Director, The Institute of Politics at Harvard University
John F. Kennedy School of Government

US Public Policies on Nutrition in the Future

Obesity is not about pointing blame, especially where children are concerned. What can we be doing? To the extent possible, consumer groups, health care professionals, academia, industry, etc., should be involved in the revision process for the Dietary Guidelines and Food Guide Pyramid. The medical community needs to work with the education community to stress the importance of physical activity and healthy foods. The school lunch program is not getting the attention that it needs and schools do not have enough funds for basic functions. Illinois is the only state that mandates physical activity. Industry should get together and decide how to advertise to children, primarily during morning programs, so that the government may not need to get involved.

Joel Hirschhorn, M.D., Ph.D.
Assistant Professor of Genetics and Pediatrics
Harvard Medical School/Children’s Hospital
Associate Member, MIT Broad Institute

Genetics of Obesity: What do we know?

Obesity is multi-factorial. Heredity plays a strong role, based on twin and family studies, with estimates that about 50% of the variation within a population is due to inherited genetic factors. There are DNA sequences in the population that increase or decrease susceptibility to obesity, but we do not know the pathways these genes affect. There is a well-established association between rare variation in MC4R and early-onset, severe obesity. Numerous genes have common variants that have been reported to be associated with obesity, but none have been consistently replicated. A meta-analysis of association studies shows a sizable fraction (but less than half) of reported gene-disease associations are likely correct, so some of these previous reports for obesity will likely turn out to be correct. Genetic effects are likely to be modest, and therefore large study sizes will be needed to detect them reliably. Clues to the genes underlying obesity abound, but no genes have been definitely identified that contribute to common obesity. There is reason to be optimistic for the near future, as more genetic and genomic tools to find these genes become available.

Frank Hu, M.D., Ph.D.
Assistant Professor
Department of Nutrition
Harvard University School of Public Health

Role of Protein in Weight Loss Diets

There are many popular high protein diets. The premise of such diets is that higher amounts of protein will facilitate weight loss, but supporting evidence is limited so far. However, it is known that protein induces higher TEF (thermal effect of foods) compared to carbohydrates and fats. The rise in TEF is largely attributable to amino acid synthesis, but also to increased urea production and glucogenesis. It takes more calories to burn a 30% protein diet than a 15% protein diet. Although it is difficult to measure satiety, most studies found increased satiety and decreased hunger with higher protein diets (versus high fat or high carbohydrate diets). Does this mean that increased protein will lead to decreased energy intake at the next meal? Most studies show about a 10% decrease in energy intake (about 200 calories on a daily diet of 2000 calories). There is some evidence of greater fat loss with a higher protein diet. Limited data suggest that a moderately high amount of protein may have beneficial effects on blood lipids and cardiovascular disease. But a word of caution: choose the low saturated fat animal sources of protein such as lean meat and chicken, seafood, tuna, etc. Increased consumption of processed meats can be associated with an increased relative risk for type 2 diabetes and certain forms of cancers. Short term, a higher protein diet is convincing—increased satiety, decreased lipids, cholesterol, insulin, and increased energy expenditure—but long-term studies are needed. Twenty to twenty-five percent protein can be recommended to replace refined carbohydrate and sugar (choose fish, poultry, low fat dairy, nuts, egg whites, peanut butter, etc.)

John M. Jakicic, Ph.D.
Associate Professor
Chair, Department of HPRED
Director, Physical Activity and Weight Management Research Center
University of Pittsburgh

Physical Activity and Obesity

Studies show that physical activity is important to health, regardless of body weight
The relative risk of death from physical activity is comparable to that of smoking, BMI, and blood pressure and needs attention from clinicians. There is a misconception that you have to be in "marathon" shape to get health benefits from physical activity<modest fitness can yield great health benefits. Weight loss and maintenance is significantly enhanced with 150 to 200 minutes per week when combined with changes in eating behavior, but a change in eating behavior combined with approximately 300 minutes per week of moderate intensity physical activity further improves long-term weight loss. The effect of resistance exercise alone has not been shown to significantly decrease body weight nor fat mass as has been speculated. However, resistance exercise is important because it may allow obese people to increase functionality to get out of bed, walk, etc., which in turn can increase total physical activity. Evidence suggests that short bouts of physical activity may be beneficial because it allows individuals to fit some activity into each day rather than miss by trying to fit along bout of exercise. So, for best weight loss, the key is energy balance that considers increasing physical activity and decreasing how much food is consumed. Thus, the key question is: How do we get people to not only adopt, but maintain these changes in behavior?

Lee M. Kaplan, M.D., Ph.D.
Assistant Professor of Medicine
Harvard Medical School
Director, MGH Weight Center
Massachusetts General Hospital

Physiology of Weight Control: Lessons from Gastric Surgery

Obesity results from a failure of normally precise weight and energy regulatory mechanisms. It reflects the combined influences of genetic background, developmental exposures and environment on these mechanisms. Even very subtle dysregulation may lead to profound weight gain over many years. For example, a consistent energy excess of 30 calories per day will generate a weight gain of more than 200 pounds during adult life. In the U.S., we now consume approximately 225 calories per day more than we did in 1970, yet on average we have gained fewer than 20 pounds during this time. Thus, Americans have on average unknowingly burned off 96-98% of those excess calories. What causes some people to burn off 100% of the excess calories and remain thin while others expend a slightly lesser percentage of the excess calories and develop obesity is still unknown. Among the available therapies for severe obesity, gastrointestinal surgery is the most effective. It results in an average loss of 70% of excess body weight during the first 1-2 years and an average loss of more than 50% of excess body weight over a lifetime. While other therapies often generate impressive weight loss over several weeks or months, fewer than 5% of individuals with severe obesity maintain substantial weight loss over the long term. Gastric bypass (GBP) surgery appears to be effective because it causes physiological changes in the weight regulatory system that lead to a reduced weight. Late after GBP, weight is remarkably stable, and patients report that they do not feel the sense of stress, hunger or deprivation that often accompanies restrictive diets. Our recent studies demonstrate that GBP decreases the intensity and frequency of hunger, increases the frequency of satiety after meals, and increases the likelihood that satiety will prevent further eating. In addition, we have found that reward-based eating, e.g., eating in response to emotion or in the absence of hunger, is dramatically diminished after GBP. In newly developed rodent models of GBP, we have been able to examine the physiological effects of surgery on weight regulation. We have found that weight loss results from a combination of decreased food intake and increased total energy expenditure, suggesting that GBP influences the activity of the weight regulatory centers in the brain. Using genetic and pharmacological manipulation, we have begun to dissect the pathways responsible for these effects. It appears that there are several, redundant systems that normally serve to protect us against starvation and that obesity reflects inappropriate activation or overexuberance of these mechanisms. The extraordinary effectiveness of GBP appears to result from its ability to influence several pathways simultaneously, avoiding the counterregulation that characterizes diet-induced weight loss. These findings suggest that effective therapy for obesity will be best achieved by combinations of different treatments rather than single agents or interventions. Further understanding of the mechanisms of weight loss after GBP will provide important clues to the causes of obesity and should facilitate development of alternative, less invasive therapies for this challenging problem.

Tomas Philpson, Ph.D.
Senior Economic Advisor, Food and Drug Administration

Government Perspective: Food Labeling

The obesity epidemic is an urgent public health issue for the Food and Drug Administration (FDA). We can learn from the experience of the FDA regarding the usefulness of food labeling as a dietary guide for Americans. Sixty to eighty percent of food shoppers say that they read the label before buying a new food item and thirty to forty percent say that the label influences their choices. But there is also confusion in reading the label and in identifying how the food fits into a healthy diet. This in turn can lead to distrust in all dietary guidance. In light of this, FDA is trying to make the food label a more effective vehicle for dietary messages. In the past several years, the standard for health claims has been loosened significantly and "qualified" heath claims are now permitted. Last August, Commissioner McClellan appointed an Obesity Working Group. For the most part, the group has focused on the immediate question of how best to persuade consumers to keep their food intake in balance with their output of energy—perhaps through the use of food labeling. For example, restaurants could list the amount of calories of meals on printed menus and menus that are posted above counters at fast-food outlets. Food manufacturers could put total product calories on a label if the product is likely to be consumed in one sitting. In addition, qualified health claims will allow more health and nutrition information to reach more consumers, as will updating the food label with trans fat information. The use of food labeling for dietary advocacy is very much a work in progress and FDA will take great care to work intensively, imaginatively, and as effectively as possible.

Barbara J. Rolls, Ph.D.
Professor and Guthrie Chair
Department of Nutritional Sciences
Pennsylvania State University

Portion Size and the Obesity Epidemic

If we are going to focus our efforts, it should be with kids. Children are probably born with the proper eating knowledge, but by age 5 they learn to respond to their plates and not their bodies. Children learn about food from their environments, including what to like, what to eat, when to eat and how much to eat. Studies with older children and adults show that increasing portions increases the amount consumed, but the same result is not seen in children. One strategy is to let children serve themselves. One study showed that when children served themselves, they ate 25% less food. Bigger portions and bigger packages increase intake in both men and women. Sixty to 70% of people say they eat everything given to them when they eat out, regardless of whether they want it or not. "Eat less" is not always the best message. Portions and energy density play a role in intake. We need to help the consumer make better choices by modifying a favorite food to help the consumer feel fuller on fewer calories. For example, choose a low-fat burger and add lettuce and tomato rather than a full-fat burger with no vegetable toppings. This will reduce calories and energy density. Academia can help overcome portion-distortion by expanding education and consumer awareness campaigns and developing interventions targeted to parents and children. From the government side, food labels should give guidance about appropriate portion sizes. In addition, government incentives could entice food manufacturers to reduce energy density and offer appropriate portions. From the food industry side, point of purchase nutrition information would help consumers make healthier choices. Industry should also consider how foods can be modified to give consumers satisfying options and good value and taste, while providing fewer calories. Controlling portion size will take cooperation between scientists, government agencies and food providers.


Donald Short
Vice President
The Coca-Cola Company

The ultimate goal of The Coca-Cola Company is to refresh the world with a broad spectrum of beverage choices that meet a variety of nutritional and hydration needs. As consumers deal with issues such as time constraints, putting their kids first and managing family health, Coca-Cola is committed to innovative solutions as it relates to the obesity issue. Product solutions include accelerated development of lower calorie drinks, smaller 8-ounce package sizes for carbonated soft drinks and a variety of fortified beverages, (micronutrient fortified drinks in South Africa, vitamin D added to calcium fortified juices, non-fat milk based beverages for schools) serving global nutrient needs. The Coca-Cola Company supports a host of nutrition education and physical activity programs such as Step With It, providing pedometers in schools, and through Mayoclinic.com which provides health tips on Minute Maid orange juice cartons. The company’s newest venture is The Beverage Institute for Health & Wellness established to help people all over the world lead healthier lives…through beverages. The Institute will support nutrition research and consumer education that will focus on the role of beverages in a healthy lifestyle. Current projects for The Beverage Institute include the role of hydration in health, alternative beverage sweeteners, capturing the natural goodness of fruits and vegetables in beverages, and beverage fortification.

Allen M. Spiegel, M.D.
Director, National Institute of Diabetes
and Digestive and Kidney Diseases
National Institutes of Health

The NIH Obesity Task Force Strategic Plan for Support of Obesity Research

Obesity is a major public health problem that has reached epidemic proportions in the past two decades. The National Institutes of Health (NIH) focuses on obesity because of its health consequences which include increased incidence of type 2 diabetes, heart disease, hypertension, stroke, some forms of cancer, asthma, gallbladder disease, osteoarthritis, and more. NIH-supported research has led to major advances in our understanding of regulation of appetite and energy balance, as well as the basis for obesity-associated morbidities. For example, fat turns out to be an important endocrine organ that secretes hormones and cytokines signaling to the brain and other organs to regulate metabolism. Obesity is an inflammatory state that can lead to cardiovascular disease among other consequences. Because of the severity and impact of the obesity epidemic, and in order to coordinate the research activities of the various NIH Institutes, an NIH Obesity Research Task Force has been established by the Director, Elias Zerhouni. The Task Force is co-chaired by Directors from NIDDK, Allen Spiegel, and NHLBI, Barbara Alving (Acting Director), and has drafted a comprehensive obesity research strategic plan (see www.obesityresearch.nih.gov). The goals of the plan are to improve treatment and prevention of obesity and its associated morbidities. New research initiatives to help reach these goals include several directed at identification of genetic, behavioral and environmental factors causing obesity, and understanding the pathogenesis of obesity and its comorbidities. Building on these initiatives are specific efforts to prevent and treat obesity in adults (e.g. worksite interventions) and in children (e.g. prevention in the pediatric primary care setting). A key NIH goal for obesity research is to integrate biologic and behavioral approaches. While the NIH alone cannot reverse the obesity epidemic, research supported by the NIH Task Force plan should provide the scientific basis for better medical, behavioral and public health approaches to this urgent problem.

Pat Verduin, Ph.D.
Senior Vice President and Director, Product Quality and Development
ConAgra Foods, Inc.

From introduction of its Healthy Choice brand in 1989 to its long history of support for child nutrition programs, ConAgra Foods has worked closely with the nutrition and food science communities to address nutrition and dietary issues. The recent history associated with diets and food fads, unsupportable industry claims, government indecision, and the latest "net carb" debate, have left consumers greatly confused. While the diet rage has shifted from counting calories to reducing fat, to the introduction of shakes and snack bars as meal replacers, and now low-carbohydrate, high protein diets, the emerging opportunity may be individualized nutrition. To seize this opportunity for the benefit of consumers and the nation’s health, the food industry, government, academia and the medical community should come together to better inform consumers, strengthen nutrition education, and develop product choices and options that help consumers meet their individual nutritional needs at different stages of life, for different levels of activity and to meet specific lifestyles. When it comes to information, industry’s plate should be centered on clear, consistent and honest product claims, labels and advertising, as well as working with retailers and restaurants to offer consumers relevant information about the products they purchase. When it comes to education, industry’s plate should be centered on promoting nutrition education at all levels from public school classes in physical education and the sciences to medical schools, and enhancing nutrition awareness at the consumer level. When it comes to product choices and options, industry can make a big difference in creating new products that meet individual nutritional needs, reformulating mature products to reduce cholesterol, saturated fats and sodium, and adding nutrients where appropriate. In doing so, industry faces the challenge of satisfying consumer expectations for taste, quality and price. The hope is that industry can develop healthier products by partnering with science-based community and government. That said, if we help consumers determine the optimum level of exercise, devise the ideal meal or diet plan, and provide reams of information, hours of education and communicate it all over and over again, only to fail to reach consumer acceptance, then we will have failed.

W. Allan Walker, M.D.
Conrad Taff Professor of Nutrition
Director Division of Nutrition, Harvard Medical School

The NIH-supported Nutrition Academic Award Program:
Innovative Teaching Strategies for Training Physicians in Clinical Nutrition

Nutrition is essential to medical education because major diseases like cardiovascular disease, diabetes, hypertension, cancer, etc., are related to a "poor" diet. American-trained doctors are not prepared to provide nutrition advice because they do not get the nutrition training they need from medical schools. The National Academies of Science recommend that medical students receive a minimum of 25 hours of nutrition education, yet the NY Times reported in 1993 that less than 40% of medical schools comply with recommendations and that 50% of medical schools are without a nutrition course. The NIH-funded Nutrition Academic Award Program (NAA) is a program created in response to a need to help medical schools with nutrition education. WAVE and REAP are two examples of programs begun at Brown University and now used at Harvard Medical School, one of 21 NAA sites across the country. WAVE is a quick tool to assess a patient’s Weight, Activity, Variety (of diet) and Excess (of diet). REAP is Rapid Eating and Activity Assessment- a ten minute survey that patients fill out in the waiting room and used for immediate feedback in-house. NAA Program funding will run out in 2005.

Rena Wing, Ph.D.
Brown University
The Miriam Hospital
Department of Psychiatry and Human Behavior

Successful Weight Loss Maintenance

About 20% of overweight individuals meet the criteria for successful weight loss maintenance, which is defined as individuals who have intentionally lost at least 10% of their body weight and have kept it off for at least one year. Based on the National Weight Control Registry, a registry of over 4000 individuals who have been successful at long term weight loss maintenance, it appears that there are many different approaches to weight loss, but the strategies they report for successful weight loss maintenance are quite consistent: 1) a low-calorie, low-fat diet; 2) high levels of physical activity (average of 2545 calories expended per week for women and 3293 for men); and 3) frequent self-monitoring; 4) 76% eat breakfast. In addition, there are certain factors associated with weight loss maintenance: higher duration of maintenance, lower disinhibition and depression, medical trigger such as a heart attack or close friend/relative diagnosed with type 2 diabetes, and maintaining a consistent eating pattern. Randomized clinical trials of weight loss maintenance suggest that the combination of diet and exercise is key and that the use of meal replacement products and high levels of physical activity may be beneficial. Based on large trials such as the DPP (Diabetes Prevention Program) study, it is clear that even modest weight loss can have a major impact on health.