Consensus Study Report

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International Standard Book Number-13: 978-0-309-69159-8
International Standard Book Number-10: 0-309-69159-1
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2023. Evaluating the process to develop the Dietary Guidelines for Americans, 2020–2025: Final report. Washington, DC: The National Academies Press. https://doi.org/10.17226/26653.

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COMMITTEE ON EVALUATING THE PROCESS TO DEVELOP THE DIETARY GUIDELINES FOR AMERICANS, 2020–2025

KATHLEEN M. RASMUSSEN (Chair), Cornell University, Ithaca, New York

STEPHANIE A. ATKINSON, McMaster University, Hamilton, Ontario, Canada

KELLY D. BROWNELL, Duke University, Durham, North Carolina

MARTHA S. FIELD, Cornell University, Ithaca, New York

SHARON I. KIRKPATRICK, University of Waterloo, Waterloo, Ontario, Canada

BRUCE Y. LEE, City University of New York, New York

DOUGLAS A. LUKE, Washington University, St. Louis, Missouri

ESTHER F. MYERS, Myers Consulting, St. Louis, Missouri

EMILY OKEN, Harvard University, Boston, Massachusetts

JOSÉ M. ORDOVÁS, Tufts University, Boston, Massachusetts

A. CATHARINE ROSS, Pennsylvania State University, University Park, Pennsylvania

JOHN B. WONG, Tufts University School of Medicine, Boston,

Massachusetts

Health and Medicine Division Staff

KATHERINE M. DELANEY, Program Officer

NICOLE CUNNINGHAM, Research Assistant (until August 2022)

MELANIE ARTHUR, Senior Program Assistant

ANN L. YAKTINE, Food and Nutrition Board Director

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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 charge. The review comments and draft manuscript remain confidential to protect the integrity of the process.

We thank the following individuals for their review of this report:

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the content of the report nor did they see the final draft before its release. The

review of this consensus study report was overseen by SUSAN J. CURRY, University of Iowa, and SUZANNE P. MURPHY, University of Hawai‘i Cancer Center. They were responsible for making certain that an independent examination of this report was carried out in accordance with standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the editors and the National Academies.

Preface

The Dietary Guidelines for Americans (DGA) are foundational for the development of federal nutrition policy and programs in the United States and are of great interest to individuals from policy makers to the general public. A prior edition of the guidelines generated questions about the process used to update the DGA over a 5-year cycle. In response, Congress mandated that a comprehensive review of the entire process of developing the DGA be carried out by the National Academies of Sciences, Engineering, and Medicine (the National Academies). The final report, Redesigning the Process for Establishing the Dietary Guidelines for Americans (the 2017 National Academies report), was released in 2017 and included seven recommendations directed at improving this process.

Subsequently, in 2021, Congress mandated that the National Academies convene a new ad hoc committee to assess how well the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (HHS) implemented these recommendations. In particular, this committee was asked to answer three overarching questions:

1. How did the process used to develop the 2020–2025 DGA, compare to the seven recommendations included in the 2017 National Academies report? (Task 1)
2. Did the criteria used to include scientific studies used to inform the 2020–2025 DGA ensure that the evidence base was current, rigorous, and generalizable or applicable to public health nutrition guidance? (Task 2)

3. How would the process with full implementation of the seven recommendations included in the 2017 National Academies report compared to the process used to develop the 2020–2025 DGA have affected the timeline, cost, and/or integrity of the more recently issued guidelines? (Task 3)

The first product of the Committee on Evaluating the Process to Develop the Dietary Guidelines for Americans, 2020–2025 was its midcourse report titled Evaluating the Process to Develop the Dietary Guidelines for Americans, 2020–2025: A Midcourse Report, which was released in 2022. In that report, the committee provided its preliminary analysis of data relative to Tasks 1 and 2.

In this, its final report, the committee presents its analysis of data relative to Task 3 and its overall conclusions and perspectives in response to its Statement of Task. Given that Task 3 built on Task 1, the evidence, and the committee’s findings and conclusions for Task 3 presented here include and supersede those for Task 1 presented in the midcourse report. No additional work was done on Task 2, so the findings for this task stand as published in the midcourse report.

To approach Task 3, the committee considered the DGA timeline and the cost to implement each recommendation as constraints to the process. The committee identified scientific rigor as necessary to achieve integrity as an outcome of the DGA process and identified both rigor and integrity as essential to the trustworthiness of the DGA process and product. The committee’s work was grounded in evidence from publications in the peer-reviewed literature that describe innovations in the 2020–2025 DGA as well as changes to the process of preparing these guidelines made in response to the 2017 National Academies report. In open meetings, the committee received additional information from key staff members at USDA and HHS as well as members of the Dietary Guidelines Advisory Committee (DGAC) and the chairperson of the 2017 National Academies report committee. The Departments also provided written responses to questions posed by the committee. The committee made extensive use of the information contained in the numerous federal websites that describe the DGA, the basis for the guidelines, and how they were developed. This research also covered the work of the DGAC. It is noteworthy that this report is not an assessment of the merits of the 2020–2025 DGA, but rather, it is an assessment of the process by which they were created relative to the specific recommendations of the 2017 National Academies report.

During its analysis, the committee considered the values on which the recommendations in the 2017 National Academies report were based. When conducting its analysis, the committee was cognizant of the timing of the release of the 2017 National Academies report relative to the time-

line required to produce the 2020–2025 DGA. This meant that it was, in some cases, not feasible to implement the 2017 National Academies report recommendations during this DGA cycle. The committee was guided by scientific evidence when it was available. When a recommendation was not implemented, the committee used its scientific expertise and judgment to reach its conclusions because implementation could have taken many forms. The committee assessed the implementation of the 2017 National Academies report’s recommendations in the spirit of making a strong process even better.

In its work, the committee identified areas the Departments have made substantial progress toward or nearly completed implementation of the recommendations. There were also cases when the implementation of recommendations was not completed or had not begun during the 2020–2025 DGA cycle. In the committee’s opinion, these situations represent opportunities to make important investments in continuing the redesign of the structure and process to create the DGA. Moreover, it is essential to do so because the 2017 National Academies report recommendations are expected to be effective and impactful when fully implemented.

I am especially grateful to the members of the committee, Stephanie A. Atkinson, Kelly D. Brownell, Martha S. Field, Sharon I. Kirkpatrick, Bruce Y. Lee, Douglas A. Luke, Esther F. Myers, Emily Oken, José M. Ordovás, A. Catharine Ross, and John B. Wong (see Appendix A) for their exceptional dedication in producing this final report in response to the congressional mandate. The committee offers its thanks to Julie Obbagy and Eve Stoody from USDA and Janet de Jesus from HHS, and their staff members, for providing essential information to the committee. The committee also offers its thanks to the 2020 DGAC chair and co-chair Barbara Schneeman and Ronald Kleinman, as well as the 2017 National Academies report chair Robert Russell for meeting with the committee and providing their insight to the process. Finally, the committee thanks the National Academies’ study staff, Katherine M. Delaney, study director; Nicole Cunningham, research assistant; Melanie Arthur, senior program assistant, and Ann L. Yaktine, director of the Food and Nutrition Board, for their assistance to the committee in carrying out its task.

Kathleen M. Rasmussen, Chair
Committee on Evaluating the Process to Develop the
Dietary Guidelines for Americans, 2020–2025

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Contents

ACRONYMS AND ABBREVIATIONS

SUMMARY

1 INTRODUCTION

Background for the Study

The Committee’s Task

Organization of the Final Report

References

2 THE PROCESS TO CREATE THE DIETARY GUIDELINES FOR AMERICANS IS BOTH COMPLICATED AND COMPLEX: BACKGROUND AND CONTEXT FOR TASK 3

Complexities Related to Trust in Nutrition Science

Complexities Related to the Process of Creating the Dietary Guidelines for Americans

Supporting the Rigor and Integrity of the Dietary Guidelines by Addressing the Complexities Through Systems Science

Conclusions

References

3 METHODOLOGICAL APPROACH TO THE TASK

The Committee’s Interpretation of Task 3

Methodological Approach to Task 3

References

4 ASSESSING THE POTENTIAL IMPLICATIONS OF FULLY IMPLEMENTING THE 2017 RECOMMENDATIONS TO REDESIGN THE PROCESS TO ESTABLISH THE DIETARY GUIDELINES FOR AMERICANS: COMMITTEE FINDINGS AND CONCLUSIONS

Criticisms That Led to the 2017 National Academies Report Recommendations

Organization of the Chapter

Recommendation 1

Recommendation 2

Recommendation 3

Recommendation 4

Recommendation 5

Recommendation 6

Recommendation 7

Task 3 Conclusions for Each 2017 Report Recommendation

Task 3 Crosscutting Conclusions

Task 3 Overall Conclusions

References

5 CONCLUDING REMARKS

Context for the Committee’s Conclusions Relative to the Dietary Guidelines for Americans

Summary of Committee Conclusions for Each Task

How the Approaches of USDA and HHS Meet the Recommendations from the 2017 National Academies Report

Implementation of the Values from the 2017 National Academies Report

The Committee’s Overall Perspective on Its Work

References

APPENDIXES

A Committee Member Biographies

B Elements of the 2020–2025 Dietary Guidelines for Americans Process

C Data Sources Used by the 2020 Dietary Guidelines Advisory Committee

D Open Session Materials

Acronyms and Abbreviations

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