美国人防癌抗癌健康饮食和运动锻炼指南

DOI: 10.3322/canjclin.56.5.254 2006;56;254-281 CA Cancer J Clin Nutrition and Physical Activity Guidelines Advisory Committee Gansler, Kimberly S. Andrews, Michael J. Thun and The American Cancer Society 2006 Lawrence H. Kushi, Tim Byers, Colleen Doyle, Elisa V. Bandera, Marji McCullough, Ted Activity Prevention: Reducing the Risk of Cancer With Healthy Food Choices and Physical American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer This information is current as of July 24, 2009 http://caonline.amcancersoc.org/cgi/content/full/56/5/254 the World Wide Web at: The online version of this article, along with updated information and services, is located on http://caonline.amcancersoc.org/subscriptions/individuals only): , go to (USCA: A Cancer Journal for CliniciansTo subscribe to the print issue of ISSN: 1542-4863. OnlineAtlanta GA 30303. (©American Cancer Society, Inc.) All rights reserved. Print ISSN: 0007-9235. is owned, published, and trademarked by the American Cancer Society, 250 Williams Street NW,CA Wiley-Blackwell. A bimonthly publication, it has been published continuously since November 1950. is published six times per year for the American Cancer Society byCA: A Cancer Journal for Clinicians by on July 24, 2009 (©American Cancer Society, Inc.) ca o nline.am cancersoc.org D ow nloaded from American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer Prevention: Reducing the Risk of Cancer With Healthy Food Choices and Physical Activity* Lawrence H. Kushi, ScD; Tim Byers, MD, MPH; Colleen Doyle, MS, RD; Elisa V. Bandera, MD, PhD; Marji McCullough, ScD, RD; Ted Gansler, MD, MBA; Kimberly S. Andrews; Michael J. Thun, MD, MS; and The American Cancer Society 2006 Nutrition and Physical Activity Guidelines Advisory Committee ABSTRACT The American Cancer Society (ACS) publishes Nutrition and Physical Activity Guidelines to serve as a foundation for its communication, policy, and community strategies and ultimately, to affect dietary and physical activity patterns among Americans. These Guidelines, published every 5 years, are developed by a national panel of experts in cancer research, pre- vention, epidemiology, public health, and policy, and as such, they represent the most current scientific evidence related to dietary and activity patterns and cancer risk. The ACS Guidelines include recommendations for individual choices regarding diet and physical activity patterns, but those choices occur within a community context that either facilitates or interferes with healthy behaviors. Community efforts are essential to create a social environment that pro- motes healthy food choices and physical activity. Therefore, this committee presents one key recommendation for community action to accompany the four recommendations for individ- ual choices to reduce cancer risk. This recommendation for community action recognizes that a supportive social environment is indispensable if individuals at all levels of society are to have genuine opportunities to choose healthy behaviors. The ACS Guidelines are consistent with guidelines from the American Heart Association and the American Diabetes Association for the prevention of coronary heart disease and diabetes, as well as for general health promo- tion, as defined by the Department of Health and Human Services’ 2005 Dietary Guidelines for Americans. (CA Cancer J Clin 2006;56:254–281.) © American Cancer Society, Inc., 2006. THE IMPORTANCE OF WEIGHT CONTROL, PHYSICAL ACTIVITY, AND DIET IN CANCER PREVENTION For the great majority of Americans who do not use tobacco, weight control, dietary choices, and levels of phys- ical activity are the most important modifiable determinants of cancer risk.1–3 Evidence suggests that one-third of the more than 500,000 cancer deaths that occur in the United States each year can be attributed to diet and physical activity habits, including overweight and obesity, while another third is caused by exposure to tobacco products. Although genetic inheritance influences the risk of cancer, and cancer arises from genetic mutations in cells, most of the variation in cancer risk across populations and among individuals is due to factors that are not inherited.4 Behaviors Guidelines on Nutrition and Physical Activity 254 CA A Cancer Journal for Clinicians Dr. Kushi is Associate Director for Etiology and Prevention Research, Kaiser Permanente, Oakland, CA. Dr. Byers is Professor, Department of Preventive Medicine and Biometrics; and Deputy Director, University of Colorado Cancer Center, Aurora, CO. Ms. Doyle is Director, Nutrition and Physical Activity, Cancer Control Science, American Cancer Society, Atlanta, GA. Dr. Bandera is Assistant Professor, The Cancer Institute of New Jersey, New Brunswick, NJ. Dr. McCullough is Nutritional Epi- demiologist, American Cancer Society, Atlanta, GA. Dr. Gansler is Director of Medical Content, Health Promotions, American Cancer Society, Atlanta, GA. Ms. Andrews is a Research Assoc- iate, Cancer Control Science, American Cancer Society, Atlanta, GA. Dr. Thun is Vice President, Epidem- iology and Surveillance Research, American Cancer Society, Atlanta, GA. This article is available online at http://CAonline.AmCancerSoc.org *The following report was approved by the American Cancer Society National Board of Directors on May 19, 2006. by on July 24, 2009 (©American Cancer Society, Inc.) ca o nline.am cancersoc.org D ow nloaded from such as avoiding exposure to tobacco products, maintaining a healthy weight, staying physically active throughout life, and consuming a healthy diet can substantially reduce one’s lifetime risk of developing cancer.5–8 These same behaviors are also associated with decreased risk of developing cardiovascular disease. Although these healthy choices are made by individuals, they may be facilitated or impeded by the social and physical environment in which people live. OVERVIEW OF THE GUIDELINES The ACS publishes Nutrition and Physical Activity Guidelines to advise health care pro- fessionals and the general public about dietary and other lifestyle practices that reduce cancer risk.9,10 These Guidelines, updated in 2006 by the ACS Nutrition and Physical Activity Guide- lines Advisory Committee, are based on synthe- sis of the current scientific evidence on diet and physical activity in relation to cancer risk. The Committee reviewed evidence from human pop- ulation studies and laboratory experiments pub- lished since the last release of the Guidelines in 2001. The Committee also considered other comprehensive reviews of diet, obesity, and phys- ical inactivity in relation to cancer. For some aspects of nutrition, the most thorough review was the 1997 World Cancer Research Fund/ American Institute for Cancer Research mono- graph; for others, such as physical activity, obe- sity, and fruit and vegetable consumption, there have been more recent comprehensive re- views.3,11,12 In weighing the evidence from ran- domized controlled trials (RCTs), the Committee considered the findings in relation to the design of the trial, the specific question being addressed, and the importance of the trial results in the context of other evidence from human popu- lations. Prospective cohort studies were weighted more heavily than case-control studies, espe- cially when results were available from several cohorts. Population-based case-control studies with at least 200 cases of cancer were consid- ered more informative than smaller or hospital- based case-control studies. Studies that adjusted for total energy intake, considered other dietary factors, and controlled for other known risk factors were considered more credible than those that failed to meet these criteria. For many issues concerning nutrition and cancer, the evidence is not definitive, either because the published results are inconsistent, and/or because the methods of studying nutri- tion and chronic disease in human populations are still in evolution. Part of the uncertainty has resulted from studies that focus on specific nutri- ents or foods in isolation, thereby oversimplify- ing the complexity of foods and dietary patterns; the importance of dose, timing, and duration of exposure; and the large variations in nutritional status among human populations. Nutritional research is equally challenging in RCTs, gen- erally considered the gold standard for scientific conclusions. Studies may fail to find an effect if the intervention begins too late in life, is too small, or if the follow up is too short for a ben- efit to appear. No single trial can resolve all of the questions that are relevant to the potential effects of nutrition throughout the lifespan. Moreover, many important questions about how diet, phys- ical activity, and obesity relate to cancer cannot presently be addressed in RCTs. For example, randomized trials of weight loss in relation to cancer risk are severely constrained by the cur- rent lack of effective behavioral or pharmaco- logic approaches to help people lose weight and sustain a healthy weight. The cost and difficulty of randomized trials to determine the long-term consequences of interventions that begin in infancy and extend for many years preclude long- term experimental interventions. Interventions are ethical only if they can plausibly improve the health of the participants. Although it might be easier to motivate people to increase their weight by consuming more calories and/or fat and by decreasing their physical activity, such studies are clearly unethical. Inferences about the many complex interre- lationships among body weight, physical activ- ity, diet, and cancer risk are therefore based, for the most part, on a combination of clinical tri- als and observational studies coupled with advanc- ing understanding of the biology of cancer. These Guidelines are based on the totality of evidence from all sources, taking into account both the potential health benefits and possible risks from the intervention. No diet or lifestyle pattern can 255Volume 56 • Number 5 • September/October 2006 CA Cancer J Clin 2006;56:254–281 by on July 24, 2009 (©American Cancer Society, Inc.) ca o nline.am cancersoc.org D ow nloaded from Guidelines on Nutrition and Physical Activity 256 CA A Cancer Journal for Clinicians guarantee full protection against any disease; the potential health benefit represents a decreased likelihood that the disease will occur, not a guar- antee of total protection. These Guidelines pro- vide a concise and understandable summary of the existing scientific information about weight control, physical activity, and nutrition in rela- tion to cancer. The ACS Guidelines are consis- tent with guidelines established for cancer prevention by other countries8; those from the American Heart Association and American Diabetes Association for the prevention of coro- nary heart disease and diabetes13,14; as well as for general health promotion, as defined by the 2005 Dietary Guidelines for Americans.15 In addition to recommendations regarding individual choices related to weight control, physical activity, and diet, the ACS Guidelines underscore what communities can and should do to facilitate healthy eating and physical activ- ity behaviors (Table 1). Community efforts are essential to create a social environment that pro- motes healthy food choices and physical activ- ity. Thus, the recommendation for community action recognizes that a supportive social envi- ronment is indispensable if individuals at all levels of society are to have genuine opportuni- ties to choose healthy behaviors. AMERICAN CANCER SOCIETY GUIDELINES FOR NUTRITION AND PHYSICAL ACTIVITY Recommendations for Community Action Social, economic, and cultural factors strongly influence individual choices about diet and phys- ical activity. Although many Americans would like to adopt a healthy lifestyle, many encounter sub- stantial barriers that make it difficult to follow diet and activity guidelines. Indeed, current trends toward increasing portion sizes,16–19 as well as the consumption of high-calorie convenience foods, beverages, and restaurant meals, and declin- ing levels of physical activity are contributing to an obesity epidemic among Americans of all ages and across all population segments.15,20,21 Longer workdays and more households with multiple wage earners reduce the amount of time avail- able for preparation of meals, with a resulting shift toward increased consumption of high- calorie food outside the home—frequently less nutritious than foods prepared at home.22 Large TABLE 1 American Cancer Society (ACS) Guidelines on Nutrition and Physicial Activity for Cancer Prevention ACS Recommendations for Individual Choices Maintain a healthy weight throughout life. • Balance caloric intake with physical activity. • Avoid excessive weight gain throughout the life cycle. • Achieve and maintain a healthy weight if currently overweight or obese. Adopt a physically active lifestyle. • Adults: engage in at least 30 minutes of moderate to vigorous physical activity, above usual activities, on 5 or more days of the week. Forty-five to 60 minutes of intentional physical activity are preferable. • Children and adolescents: engage in at least 60 minutes per day of moderate to vigorous physical activity at least 5 days per week. Consume a healthy diet, with an emphasis on plant sources. • Choose foods and beverages in amounts that help achieve and maintain a healthy weight. • Eat five or more servings of a variety of vegetables and fruits each day. • Choose whole grains in preference to processed (refined) grains. • Limit consumption of processed and red meats. If you drink alcoholic beverages, limit consumption. • Drink no more than one drink per day for women or two per day for men. ACS Recommendations for Community Action Public, private, and community organizations should work to create social and physical environments that support the adoption and maintenance of healthful nutrition and physical activity behaviors. • Increase access to healthful foods in schools, worksites, and communities. • Provide safe, enjoyable, and accessible environments for physical activity in schools, and for transportation and recreation in communities. by on July 24, 2009 (©American Cancer Society, Inc.) ca o nline.am cancersoc.org D ow nloaded from portion sizes and calorie-dense foods are used extensively in marketing by restaurants, supermar- kets, and food companies.16–19 Reduced leisure time, increased reliance on automobiles for trans- portation, and increased availability of electronic entertainment and communications media all contribute to reduced physical activity.20,21 Increasing evidence indicates associations between the built environment and obesity and physical activity levels.23,24 Poor access to sidewalks, parks, and recreation facilities is associated with greater obesity risk,25 whereas neighborhoods that facil- itate walking and safe physical recreation have lower obesity prevalence.23 The increase in obesity and physical inactiv- ity is of particular concern for a number of pop- ulation groups, including children, who are establishing lifetime behavioral patterns that affect health, and lower-income populations, who face additional problems because nearby stores often lack affordable and attractive healthy foods, and safety concerns limit opportunities for physical activity. Facilitating improved diet and increased phys- ical activity patterns in communities will require multiple strategies and bold action, ranging from the implementation of community, worksite, and other health promotion programs to policies that affect community planning, transportation, school- based physical education, and food services. Par- ticular efforts will be needed to ensure that all population groups have access to healthy food choices and opportunities for physical activity. Public and private organizations at local, state, and national levels will need to develop new poli- cies and to reallocate or expand resources to facil- itate necessary changes. Health care professionals and community leaders, in particular, have new opportunities to provide leadership and to pro- mote policy changes in their communities. Lessons learned from the tobacco epidemic exemplify the power of social context in chang- ing health behaviors. Adult per-capita cigarette consumption increased steeply from 1910 until 1964, when the first US Surgeon General Report publicized the health hazards of smoking. However, public education alone produced only a gradual decrease in cigarette consumption from 1964 through the early 1980s. It was the subsequent introduction of community-wide policy approaches that produced much larger reductions in cigarette smoking among children and adults, beginning in the mid-1980s. These included restrictions on cigarette advertising, increases in the price of tobacco products through taxation, laws preventing exposure to secondhand smoke in public places, and restrictions on the access of children to tobacco products. Only recently have communities begun to consider policy approaches that might promote better nutrition and physi- cal activity at the population level. Public, pri- vate, and community organizations are now considering policy measures and strategies that could help individuals choose healthier patterns of nutrition and physical activity (Table 1). Recommendations for Individual Choices Approximately two-thirds of Americans are overweight or obese. The percentage of children, adolescents, and adult men who are overweight or obese has continued to increase through 2004, although the trend has now stabilized in adult women.26 In addition, many Americans are less physically active than is optimal for health. There is no longer serious medical debate about whether obesity, the prevalence of which has doubled in the last 25 years, constitutes a major health prob- lem in the United States, increasing the risk of several cancers as well as of coronary heart dis- ease, type 2 diabetes, and other medical prob- lems. For most people in the United States, weight gain results from a combination of excessive caloric intake and inadequate physical activity. Thus, while there continues to be genuine scientific uncertainty about how specific aspects of excess adiposity, excessive energy intake, and physical inactivity relate to cancer, there is no debate about whether these constitute a serious and growing health problem. These Guidelines therefore empha- size the importance of maintaining a healthy body weight, adopting a physically active lifestyle, and consuming a healthy diet, particularly within the context of weight management. 1. Maintain a Healthy Weight Throughout Life. • Balance caloric intake with physical activity. • Avoid excessive weight gain throughout the life cycle. 257Volume 56 • Number 5 • September/October 2006 CA Cancer J Clin 2006;56:254–281 by on July 24, 2009 (©American Cancer Society, Inc.) ca o nline.am cancersoc.org D ow nloaded from Guidelines on Nutrition and Physical Activity 258 CA A Cancer Journal for Clinicians • Achieve and maintain a healthy weight if cur- rently overweight or obese. Body Weight and Cancer Risk In the United States, overweight and obesity contribute to 14% to 20% of all cancer-related mortality.27 Overweight and obesity are clearly associated with increased risk for developing many cancers, including cancers of the breast in postmenopausal women,3,27–33 colon, endo- metrium, adenocarcinoma of the esophagus, and kidney. Evidence is highly suggestive that obe- sity also increases risk for cancers of the pan- creas, gallbladder, thyroid, ovary, and cervix, and for multiple myeloma, Hodgkin lymphoma, and aggressive prostate cancer.3,27–33 These find