Redesigning the Process for Establishing the
Dietary Guidelines for Americans
Committee to Review the Process to Update the
Dietary Guidelines for Americans
Food and Nutrition Board
Health and Medicine Division
A Consensus Study Report of
THE NATIONAL ACADEMIES PRESS
Washington, DC
www.nap.edu
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International Standard Book Number-13: 978-0-309-46482-6
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Digital Object Identifier: https://doi.org/10.17226/24883
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2017. Redesigning the process for establishing the Dietary Guidelines for Americans. Washington, DC: The National Academies Press. doi: https://doi.org/10.17226/24883.
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COMMITTEE TO REVIEW THE PROCESS TO UPDATE THE DIETARY GUIDELINES FOR AMERICANS
ROBERT M. RUSSELL (Chair), Professor Emeritus, Nutrition and Medicine, Tufts University School of Medicine, Boston, Massachusetts
JAMY ARD, Professor, Department of Epidemiology and Prevention; Co-Director, Wake Forest Baptist Health Weight Management Center, Wake Forest University Baptist Medical Center, Winston-Salem, North Carolina
STEPHANIE A. ATKINSON, Professor, Pediatrics, McMaster University, Hamilton, Ontario
CAROL J. BOUSHEY, Associate Researcher, Professor, Cancer Epidemiology Program; Director, Nutrition Support Shared Resource, University of Hawaii Cancer Center, Honolulu
SUSAN M. KREBS-SMITH, Chief, Risk Factor Assessment Branch, Epidemiology and Genomics Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, Maryland
JOSEPH LAU, Professor Emeritus, Center for Evidence Synthesis in Health, Department of Health Services, Policy & Practice, Brown University School of Public Health, Providence, Rhode Island
BRUCE Y. LEE, Director, Operations Research, International Vaccine Access Center; Executive Director, Global Obesity Prevention Center; Associate Professor, International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
JOANNE R. LUPTON, Distinguished Professor Emerita, Texas A&M University, College Station
SALLY C. MORTON, Dean, College of Science, Virginia Tech, Blacksburg
NICOLAAS P. PRONK, President, HealthPartners Institute; Chief Science Officer, HealthPartners, Minneapolis, Minnesota
SUSAN B. ROBERTS, Director, Energy Metabolism Laboratory and Professor of Nutrition, U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University; Professor of Psychiatry and Staff Member in Pediatrics, Tufts Medical School, Boston, Massachusetts
A. CATHARINE ROSS, Professor, Nutrition and Physiology; Dorothy Foehr Chair and Professor, Department of Nutritional Sciences, The Pennsylvania State University, University Park
___________________
NOTE: See Appendix G, Disclosure of Conflicts of Interest.
BARBARA O. SCHNEEMAN, Emeritus Professor of Nutrition, Department of Nutrition and Department of Food Science and Technology, University of California, Davis
MARTÍN J. SEPÚLVEDA, IBM Fellow, Retired IBM Vice President of Health Systems and Policy Research, Watson Research Laboratory, IBM Corporation, St. Augustine, Florida
Health and Medicine Division Study Staff
SAMANTHA M. CHAO, Study Director
MEGHAN E. QUIRK, Senior Program Officer
MEREDITH J. YOUNG, Senior Program Assistant
ANNA BURY, Research Associate
ANN L. YAKTINE, Director, Food and Nutrition Board
Reviewers
This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.
We thank the following individuals for their review of this report:
CHERYL ACHTERBERG, The Ohio State University
ALICIA CARRIQUIRY, Iowa State University
WILLIAM H. DIETZ, The George Washington University
CHRISTINA ECONOMOS, Tufts University
JOHN W. ERDMAN, JR., University of Illinois at Urbana-Champaign
PETER BARTON HUTT, Covington & Burling LLP
RONALD M. KRAUSS, Children’s Hospital Oakland Research Institute and University of California, San Francisco
PENNY KRIS-ETHERTON, The Pennsylvania State University
SUZANNE P. MURPHY, Emeritus, University of Hawaii Cancer Center
ESTHER F. MYERS, EF Myers Consulting, Inc.
DEBORAH L. O’CONNOR, University of Toronto
ROBERT C. POST, Chobani Nutrition Center, Chobani, LLC, and formerly with the U.S. Department of Agriculture Center for Nutrition Policy and Promotion
HOLGER J. SCHÜNEMANN, McMaster University
PAUL SHEKELLE, RAND Corporation
PATRICK J. STOVER, Cornell University
Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report nor did they see the final draft before its release. The review of this report was overseen by SUE CURRY, University of Iowa, and JOHANNA T. DWYER, Tufts Medical Center. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.
Preface
This is the second and final installment of a report that examines and then suggests improvements for the entire process used for establishing the Dietary Guidelines for Americans (DGA). This report is a consensus product of a committee of the National Academies of Sciences, Engineering, and Medicine as mandated by Congress in the Consolidated Appropriations Act of 2016. The first report was released in February 2017 and suggested changes to be made in the selection process of members of the Dietary Guidelines Advisory Committee (DGAC). In this report, the DGAC is called the DGSAC to stand for the Dietary Guidelines Scientific Advisory Committee. This second report focuses on a process redesign in developing and updating the guidelines, beyond just the selection of members for the DGSAC. This National Academies committee was specifically asked to evaluate the process, but not to evaluate the content, recommendations, or scientific justifications used in the current or past editions of the DGA.
Over time, the role of the DGA has become two-fold: (1) they provide the public with science-based dietary advice on eating patterns that can help to reduce the risk of developing a chronic disease, and (2) they provide food-based guidance (types and composition of foods to be used) in federal nutrition programs, such as the National School Lunch Program, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program, and many others. Despite the huge amount of effort that goes into establishing the DGA, less than 10 percent of Americans actually follow the guidelines. Congress has suggested that the low
level of adherence could be the result of a lack of confidence, in part because of how the DGA have been developed and hence a low level of trust in the ultimate recommendations. Congress thus directed the U.S. Department of Agriculture (USDA) to engage the National Academies to establish this ad hoc committee to conduct a comprehensive evaluation of the processes used to establish the DGA. (The Statement of Task can be found in the Introduction in Box 1-3.)
A principal finding of this National Academies committee is that an inefficiency of effort and a lack of continuity exists between successive 5-year DGA cycles. Within a 5-year cycle, the current process allots 2 years for evaluation of the science and for making conclusions by the DGAC, and 1 year for developing the DGA Policy Report by the government. The remaining 2 years of the 5-year cycle are a period of relative inactivity. This National Academies committee believes that using the entire 5 years for work on the DGA will not only provide the opportunity for a more thorough evaluation of the science, but also allow the DGA process to become more agile, flexible, and effective—and will address more topics of interest to the general public.
Currently, topic identification, gathering of scientific data, and the synthesis and interpretation of the science all fall on the shoulders of a single DGAC to be completed within a 2-year time frame. A central recommendation of this National Academies committee is to allow for more focused and tailored groups of experts to undertake each of the functions by dividing them among several groups during the 5-year cycle. The division of functions and the use of the entire 5-year time period for work on the DGA would provide many more opportunities for stakeholder and public participation, and thus serve to insert greater transparency into the process. If the DGA omits or only accepts parts of the conclusions in the DGSAC report, a clear explanation has to be given as to why. We believe these steps would all contribute to a higher degree of integrity and thus enhance the trustworthiness of the process to develop the DGA (see Recommendations 1 and 2).
Our National Academies committee also believes it is critical that the methods used to inform the DGA be validated and appropriate to the questions being asked. After extensive evaluation, we found that the current methods being used in the DGA process—original systematic reviews; existing systematic reviews, meta-analyses, and reports; food pattern modeling; and descriptive data analysis—are indeed appropriate. However, the vetting and updating of methods could be greatly strengthened by putting out the systematic reviews done at USDA’s Nutritional Evidence Library (NEL) for external peer review before handing them over to the DGSAC (see Recommendation 3). Moreover, there should be ongoing evaluation of NEL methods and ongoing training of NEL staff
by external expert groups with greater investment made in supportive, technological infrastructure (see Recommendation 4).
The final three recommendations made by this National Academies committee (see Recommendations 5, 6, and 7) are for strengthening and adopting appropriate and strategic methodologies so as always to align with current best practices. Scientific methods are continually evolving as new ones are emerging. Food pattern modeling has been used by previous DGACs, and it was found to be very useful in elucidating food grouping nutrient profiles, for example. In the future such modeling will help to make much more sense out of the complex system of exposure that is diet, which influences health. Moreover, systems approaches (now in their infancy in the nutrition field) will help us to more clearly define the roles and limitations of diet in reducing chronic disease risk. A concentrated effort will be needed to help the DGA achieve its promise, particularly as its scope becomes broadened to include all Americans—not just healthy Americans—as well as children under 24 months and pregnant women.
As chair of the committee, I would like to thank members of the committee for their time, effort, and willingness to engage in these discussions. This National Academies Committee to Review the Process to Update the Dietary Guidelines for Americans wishes to sincerely thank the many experts who helped us with this report by giving presentations, writing comments, and reviewing our drafts. The review of this report was done by individuals chosen for their diverse perspectives as well as technical expertise, and we have greatly appreciated their input. The committee hopes actions that follow the release of this report will lead to a more transparent process, resulting in more trustworthy DGA.
Robert M. Russell, Chair
Committee to Review the Process to Update the
Dietary Guidelines for Americans
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Acknowledgments
The committee and staff would like to thank those who made presentations and statements at the public workshop held on January 10, 2017, in Washington, DC, as well as those who submitted written comments for consideration during that meeting:
Angela Amico, Center for Science in the Public Interest, on behalf of Lorrene Ritchie, University of California Nutrition Policy Institute
Tejas Bhatt, Institute of Food Technologists
Darlena Birch, National Women, Infants, and Children Association
Patricia Britten, Center for Nutrition Policy and Promotion, U.S. Department of Agriculture (retired)
Cara Brumfield, 1,000 Days
Robert Burns, Grocery Manufacturers Association
Stephanie Chang, Agency for Healthcare Research and Quality
Jeannette Crenshaw, United States Breastfeeding Committee
Janet de Jesus, National Institutes of Health
Becky Domokos-Bays, Supervisor of School Nutrition, Loudoun County, VA
Eve Essery-Stoody, U.S. Department of Agriculture
Emma Gregory, American Frozen Food Institute
Colette Heimowitz, Atkins Nutritionals, Inc.
Guy Johnson, McCormick Science Institute
Casey Keller, Global Wrigley
Mark Kennedy, Physicians Committee for Responsible Medicine
Clara Lau, National Cattlemen’s Beef Association
Susan Levin, Physicians Committee for Responsible Medicine
Sean Lucan, Albert Einstein College of Medicine
Richard Lucas, Food and Nutrition Service, U.S. Department of Agriculture
Patricia Mabry, Indiana University
David Meltzer, University of Chicago
Shawna Mercer, Centers for Disease Control and Prevention
Barbara Millen, Chair, 2015 Dietary Guidelines Advisory Committee
Suzanne Murphy, University of Hawaii Cancer Center
Julie Obbagy, U.S. Department of Agriculture
Jim O’Hara, Center for Science in the Public Interest
Sarah Ohlhorst, American Society for Nutrition
Mary Pat Raimondi, Academy of Nutrition and Dietetics
Tia Rains, Egg Nutrition Center
Kathleen Rasmussen, Cornell University
Pauline Sakamoto, Human Milk Banking Association of North America
Lee Sanders, American Bakers Association
Holger Schunemann, McMaster University
Kristen Strader, Public Citizen
Cathie Woteki, U.S. Department of Agriculture
Joan Younger, American Academy of Pediatrics Section on Breastfeeding
Tracey Ziener, Wrigley
We would like to thank those who provided written public comment to the committee. We would also like to recognize the General Services Administration for its helpful background information. In addition, there are many National Academies of Sciences, Engineering, and Medicine staff members who helped throughout the study process. The staff would like to thank Sylara Marie Cruz, Faye Hillman, Sarah Kelley, Tina Ritter, and Julie Wiltshire. Finally, we would like to thank and recognize the U.S. Department of Agriculture for sponsoring this study and for its helpful background information.
Contents
The Dietary Guidelines for Americans
Evaluation by the National Academies of Sciences, Engineering, and Medicine
2 ROLE AND PURPOSES OF THE DIETARY GUIDELINES FOR AMERICANS: EVALUATION AND FINDINGS
Clarifying the Purposes of the DGA
Findings About the Process to Update the DGA
Values to Enhance the Integrity of the Process of Developing the DGA
Consideration of Options for Implementation
4 STRENGTHENING ANALYSES AND ADVANCING METHODS USED
Strengthening Existing Analyses
5 CURRENT PROCESS FOR DEVELOPING THE DIETARY GUIDELINES FOR AMERICANS: KEY FINDINGS
Inclusion of Pregnant Women and Children from 0 to 24 Months of Age
6 CURRENT APPROACHES TO EXAMINING THE EVIDENCE: KEY FINDINGS
Overview of the Types of Research Questions and Analyses Used by the DGAC
Assessment of Systematic Review Methods
Assessment of the NEL Process for Updating Systematic Reviews
Assessment of the NEL Process for Using Existing Systematic Reviews, Meta-Analyses, and Reports
Evaluation of Methodology and Use of Food Pattern Modeling
Descriptive Data Analyses: Evaluation of Methodology and Use
7 RECENT APPROACHES TO ASSESSING NUTRITIONAL ADEQUACY AND EXPLORING CHRONIC DISEASE
Assessments of Nutrient Intake Levels of the U.S. Population by the 2005, 2010, and 2015 DGACs
Approaches Used by the 2005, 2010, and 2015 DGACs to Explore Health and Chronic Diseases
B PUBLIC WORKSHOP AGENDA AND COMMENTS
D DIETARY GUIDELINES FOR AMERICANS GUIDELINES AND KEY RECOMMENDATIONS
E ADDITIONAL INFORMATION ABOUT THE DIETARY REFERENCE INTAKES
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Acronyms and Abbreviations
AHA |
American Heart Association |
AHRQ EPC |
Agency for Healthcare Research and Quality Evidence-based Practice Centers Program |
AI |
adequate intake |
AMDR |
Acceptable Macronutrient Distribution Range |
AMSTAR |
A Measurement Tool to Assess Systematic Reviews |
ARS |
U.S. Department of Agriculture Agricultural Research Service |
ARS NND |
Agricultural Research Service National Nutrient Database for Standard Reference |
B–24 |
children from birth to 24 months |
CDC |
Centers for Disease Control and Prevention |
COI |
conflict of interest |
CSFII |
Continuing Survey of Food Intakes by Individuals |
DASH |
Dietary Approaches to Stop Hypertension |
DAT |
data analysis team |
DGA |
Dietary Guidelines for Americans |
DGAC |
Dietary Guidelines Advisory Committee |
DGPCG |
Dietary Guidelines Planning and Continuity Group |
DGSAC |
Dietary Guidelines Scientific Advisory Committee |
DRI |
Dietary Reference Intake |
EAR |
Estimated Average Requirement |
EER |
Estimated Energy Requirement |
FDA |
U.S. Food and Drug Administration |
FTE |
full-time equivalent |
HHS |
U.S. Department of Health and Human Services |
IOM |
Institute of Medicine |
NEL |
Nutrition Evidence Library |
NEL BAT |
Nutrition Evidence Library Bias Assessment Tool |
NHANES |
National Health and Nutrition Examination Survey |
NHIS |
National Health Interview Survey |
NIH |
National Institutes of Health |
P/B–24 |
pregnant women and children from birth to 24 months |
PICO |
population, intervention/exposure, comparator, and outcome of interest |
RDA |
Recommended Dietary Allowance |
SEER |
National Cancer Institute’s Surveillance, Epidemiology, and End Results |
TEP |
technical expert panel |
UL |
Tolerable Upper Intake Level |
USDA |
U.S. Department of Agriculture |
WHO |
World Health Organization |
WIC |
Special Supplemental Nutrition Program for Women, Infants, and Children |
WWEIA |
What We Eat in America |