For more than two decades, the practice of risk assessment has been applied to human public health issues, and policy makers have used the results of risk assessments in their decision-making process. Approaches for risk assessment have been developed for nonnutrients such as drugs, food additives, and pesticides, but approaches for risk assessment have received less attention in the nutrition area. Some aspects of the risk assessment approach used for nonnutrients are applicable to the assessment of risks related to nutrition (called nutritional risk assessment in this workshop summary). The overall approach, however, must be adapted and modified to take into account the unique aspects of nutrients, including the fact that both high and low nutrient intakes are associated with risk. Experience with the application of a risk assessment process to the setting of upper levels of intake for essential nutrients, for example, has uncovered a number of challenges. Adapting and developing risk assessment strategies for application in nutrition science could lead to improved approaches to the development of dietary and nutritional recommendations and thus is a topic of considerable interest.

One nonscientific but overall challenge to nutritional risk assessment relates to increasing and improving communication among experts from key disciplines in ways that could inform the nutritional risk assessment process. Among these key disciplines are nutrition, toxicology, dietary exposure assessment, economics, risk analysis, and epidemiology. How can the perspectives and methods of these diverse fields be brought together to develop more effective approaches for quantitative nutritional risk assessment? How can they be applied to a spectrum of topics related to food and nutrition—micronutrients, macronutrients, dietary supplements, whole foods, food groups, and dietary patterns? How can they help overcome the data challenges that confront nutritional risk assessors?

As a step toward improving the communication and sharing methods and information across disciplines, members of the Interagency Risk Assessment Consortium, the U.S. Health and Human Services Office of the Assistant Secretary for Planning and Evaluation, the Institute of Medicine’s Food Forum, and the International Life Sciences Institute planned the Nutritional Risk Assessment Workshop. The workshop was held on February 28 and March 1, 2007, in Washington, D.C. This workshop, which was envisioned as one in a series, focused on opening a dialogue to explore the unique questions and challenges faced by nutritionists and the potential use of risk assessment methodologies to answer them.

Specifically, the workshop served as a forum for experts from various disciplines to

• discuss the strengths and challenges of using various risk assessment approaches to inform dietary and nutritional recommendations,
• explore the use of risk assessment approaches to evaluate standards for nutrient intake and the relationship of diet and nutrition to chronic disease risk, and
• identify next steps necessary to make progress in these areas.

After a brief introduction by Catherine E. Woteki and Robert L. Buchanan, panels of experts provided an overview of risk assessment as it relates to nutrition; explored ways to share risk assessment approaches used by different groups; addressed challenges related to dietary patterns and health outcomes; identified new developments and challenges related to genetics, dietary intake assessment, and food composition data; and listed numerous data gaps. Twenty-two experts from many fields gave formal presentations, and members of the audience broadened perspectives and added information during open discussion periods. The sessions were meant to offer an organized dialogue among the experts. With this in mind, various experts presented information on a range of methodological challenges of nutritional risk assessment and on approaches that might be used to address the challenges. Many speakers mentioned the risk assessment process used to establish Tolerable Upper Intake Levels as part of the process for setting Dietary Reference Intakes. This risk assessment model appears in Figure O-1. During the wrap-up session, moderator Robert Buchanan and five other individuals—from the food industry; the federal government; and the risk assessment, consumer interest, and public health communities—provided their perspectives and highlighted challenges and potential solutions.

FIGURE O-1

Risk assessment model for nutrient toxicity.

This report is a summary of the workshop presentations and discussions. The meeting transcripts and slides used during the presentations served as the basis for the summary. Some of the content was reorganized for improved clarity. Many of the topics addressed during open discussions were closely related to topics highlighted during the wrap-up session. Therefore, most of the relevant content from the open discussions appears in Chapter 6, Perspectives on Challenges and Solutions: Summary Remarks and Suggested Next Steps.

Chapter 6 also summarizes the topics identified during the presentation and discussion as meriting more attention. Among these topics were the following:

• expanding the application of risk assessment in the processes of setting Dietary Reference Intakes and of developing various nutrition guidelines,
• incorporating new dietary intake assessment methods and elements of the evidence-based review method into nutritional risk assessment,
• addressing uncertainties more explicitly,
• achieving a more complete separation between risk assessment and risk management,
• holding a workshop to test a risk assessment model for a nutrient,
• conducting methodological research related to nutritional risk assessment, and
• developing strategies for data collection related to nutritional risk assessment.

In addition, attention was directed to the need for improved communication targeted to consumers. Some presenters and discussants expressed strong viewpoints or made recommendations. Their viewpoints and recommendations should not be viewed as workshop conclusions or recommendations.

The agenda for the workshop appears in Appendix A, and Appendix B lists the workshop participants. Appendix C contains biographical sketches for the presenters, moderators, and discussants. Appendix D lists acronyms and abbreviations used throughout this workshop.

The workshop was supported jointly by the Department of Health and Human Services Office of the Assistant Secretary for Planning and Evaluation, the Interagency Risk Assessment Consortium, the International Life Sciences Institute Research Foundation, and the Institute of Medicine’s Food and Nutrition Board’s Food Forum. The following Interagency Risk Assessment Consortium members provided financial support: Department of Health and Human Services, Food and Drug Administration, U.S. Department of Agriculture (Agricultural Research Service and the Office of Risk Assessment and Cost–Benefit Analysis). In addition, the members of the Nutritional Risk Assessment Work Group of the Interagency Risk Assessment Consortium are acknowledged for their involvement.