Dietary Guidelines Advisory Committee Research Articles

USDA Nutrition Evidence Library: Support to the 2010 Dietary Guidelines Advisory Committee

The USDA Nutrition Evidence Library (NEL) aims to be a trusted national source of evidence‐based research to inform nutrition policies and programs. NEL is also an on‐line resource that empowers scientists and decision makers by illuminating the strength of the evidence supporting nutrition policy and identifying research opportunities to facilitate improvement of Americans’ health and well‐being. The Dietary Guidelines Advisory Committee (DGAC) is charged with reviewing current science related to nutrition and health, and providing recommendations for the Dietary Guidelines for Americans. An integral part of NEL's mission is to provide ongoing support for the DGAC's scientific review process. This presentation describes the evidence‐based methodology used to support the 2010 DGAC effort. The 2010 DGAC divided the broad Dietary Guidelines into seven major topic areas, which paralleled seven subcommittees. NEL staff managed the systematic review process for each. This included assisting with question formulation; developing and implementing literature search plans; evaluating methodological rigor of studies; preparing portfolios of evidence worksheets, overview tables, and evidence summaries; and ensuring compliance with the NEL methodology each step of the way. NEL ensured that the 2010 DGAC scientific review process was consistent, rigorous, transparent, unbiased, and reproducible.

Whole Grains: Benefits and Challenges

Inclusion of whole grains (WG) in the diet is recommended in dietary guidance around the world because of their associations with increased health and reduced risk of chronic disease. WGs are linked to reduced risk of obesity or weight gain; reduced risk of cardiovascular disease (CVD), including coronary heart disease (CHD), hypertension, and stroke; improved gut health and decreased risk of cancers of the upper gut; perhaps reduced risk of colorectal cancer; and lower mortality rate. The 2005 United States Dietary Guidelines Advisory Committee has recommended that consumers make "half their grains whole." Yet, whole grains are puzzling both consumers and scientists. Scientists are trying to determine whether their health benefits are due to the synergy of WG components, individual WG components, or the fact that WG eaters make many of the recommended diet and lifestyle choices. Consumers need to understand the WG benefits and how to identify WG foods to have incentive to purchase and use such foods. Industry needs to develop great-tasting, clearly-labeled products. With both these factors working together, it will be possible to change WG consumption habits among consumers.

The New USDA: Cultivating Change

In proclaiming the week of August 23–29 National Community Gardening Week, Agriculture Secretary Tom Vilsack noted, “Community gardens provide numerous benefits including opportunities for local food production, resource conservation, and neighborhood beautification. But they also promote family and community interaction and enhance opportunities to eat healthy, nutritious foods. Each of these benefits is something we can and should strive for.” Vilsack’s statement was the latest in a string of signals in the past 7 months that suggest significant changes are afoot at the U.S. Department of Agriculture (USDA). On 29 July 2009 Agriculture Deputy Secretary Kathleen Merrigan inaugurated a new rooftop garden at the offices of the USDA Economic Research Service. In early spring, Vilsack “broke pavement” for a vegetable garden known as the People’s Garden, which was planted in front of USDA headquarters across from the National Mall. And a March 2009 planning meeting to discuss the People’s Garden and other sustainability initiatives, chaired by Vilsack, included people not typically seen at USDA meetings in the past: representatives from community garden associations, local food policy councils, botanical gardens, and the Rodale Institute, a nonprofit organization in Pennsylvania dedicated to organic farming research. Vilsack “talked about sustainability, linking agriculture, food, and human health in a way that you haven’t heard [from USDA],” recalls Rose Hayden-Smith, a fellow at the Minneapolis-based nonprofit Institute for Agriculture and Trade Policy and master gardener for the California Cooperative Extension service.

Nutrient Profiling: The New Environment

The 2005 Dietary Guidelines for Americans (DGA) recommends that individuals choose nutrient-dense foods to help meet nutrient needs without consuming excess calories, a concept that is supported by health professionals and nutrition organizations. With an increased emphasis on nutrient density, the 2005 Dietary Guidelines Advisory Committee, in their Technical Report, called for more research to develop a valid and scientific method for defining the nutrient density of foods that can ultimately be useful on labels to help people build healthier diets [1]. Nutrient profiling is the science of ranking foods based on nutrient composition. Over the past years, numerous nutrient-profiling systems have emerged to provide guidance on improving diet quality, resulting in a heightened awareness of a need for a standardized definition of nutrient density. While nutrient-profiling systems are meant to help individuals make healthier food choices, their introduction to the marketplace leaves many unanswered questions regarding both the development of a scientific definition of nutrient density and its consumer application. The goal of this article is to review the roles of nutrient density and nutrient profiling in providing consumer guidance. Specifically, this review will summarize the current nutrition environment and address the need for future research around nutrient-profiling systems as a means to define nutrient density.

Putting the Nutrient-Rich Foods Index into Practice

With approximately 2 out of 3 Americans currently overweight or obese, many continue to come up short on recommendations for certain nutrients such as calcium, magnesium, potassium, vitamin A, vitamin C, vitamin E, and fiber in their diet. Numerous attempts have been made to provide consumers with nutrient-profiling tools, such as manufacturer-specific symbols, to improve dietary selections, but many of the tools have focused on assisting consumers in making single food selections and do not provide guidance about planning total diets. In response to the 2005 Dietary Guidelines Advisory Committee's recommendation for research to define nutrient density, the Nutrient Rich Foods Coalition (NRFC) embarked on the development of a scientifically valid definition of nutrient density and consumer-driven educational tools to communicate the concept of nutrient-rich foods (NRF) to consumers. The science-based, consumer-driven NRF approach to eating may help Americans make multiple small changes in their diet that ultimately lead to better diet quality and significant improvements in public health.

Food, plant food, and vegetarian diets in the US dietary guidelines: conclusions of an expert panel

We summarize conclusions drawn from a panel discussion at the “Fifth International Congress on Vegetarian Nutrition” about the roles of and emphasis on food, plant food, and vegetarianism in current and future US dietary guidelines. The most general recommendation of the panel was that future dietary guidelines, following the lead of the 2005 Dietary Guidelines Advisory Committee, should emphasize food-based recommendations and thinking to the full extent that evidence allows. Although nutrient-based thinking and Dietary Reference Intakes (DRIs) may help ensure an adequate diet in the sense that deficiency states are avoided, the emphasis on DRIs may not capture many important nutritional issues and may inhibit a focus on foods. More generally, in the context of the conference on vegetarian nutrition, this report focuses on the history and structure of the Dietary Guidelines Advisory Committee, on various plant food–oriented recommendations that are supported by literature evidence, and on mechanisms for participating in the process of forming dietary guidelines. Among recommendations that likely would improve health and the environment, some are oriented toward increased plant food consumption and some toward vegetarianism. The literature on health effects of individual foods and whole lifestyle diets is insufficient and justifies a call for future food-oriented research, including expanding the evidence base for plant-based and vegetarian diets. The Dietary Guidelines Advisory Committee’s role should be carried forward to creation of a publicly accessible icon (eg, the current pyramid) and related materials to ensure that the science base is fully translated for the public.

Report of the Dietary Guidelines Advisory Committee Dietary Guidelines for Americans, 1995.

Report of the Dietary Guidelines Advisory Committee Dietary Guidelines for Americans, 1995.

The USDA Nutrition Evidence Library: An Evidence‐Based Resource for Development of National Nutrition Policy

The USDA Nutrition Evidence Library (NEL) plays an integral role in the development of national nutrition policy. The public health community uses a systematic, evidence‐based approach to review scientific literature for developing health promotion and prevention guidelines. The Dietary Guidelines for Americans provide science‐based advice to promote health and reduce chronic disease risk. They also serve as the foundation of national nutrition policy, programs, and educational efforts. USDA developed the NEL as a web‐based system with a set of tools to support the 2010 Dietary Guidelines Advisory Committee and other efforts to improve the nutritional well‐being of Americans. The NEL provides portfolios of evidence worksheets and management tools to support each step in the evidence‐based process, including research question formulation, literature search and sort plan development, evidence analysis and quality assessment, and rating the strength of the conclusion and recommendations. Completed reports and supporting documents will be archived in the NEL and made accessible to stakeholders and the public. This library will ensure that the relevant, timely, high‐quality, and understandable presentation of evidence is available to support translation of nutrition research into policies that promote the health of the US population.

Communicating Dietary Guidelines to a Balking Public

The 2010 Dietary Guidelines Advisory Committee is busy at work, formulating dietary guidance for Americans based on the best current nutrition science. The paper explores the communication minefield that must be navigated for the public to be appropriately informed. The authors ask, for example, if such an exercise can effectively bring about dietary behavior modification and if the public can truly learn to distinguish among the different levels of scientific certainty manifested in the research reviewed by the Committee.

The Role of Dairy in Meeting the Recommendations for Shortfall Nutrients in the American Diet

Background: The 2005 Dietary Guidelines Advisory Committee (DGAC) recognized calcium, potassium and magnesium, all found in high levels in dairy foods, among the shortfall nutrients in both children and adults’ diets.Objective: The objectives were to determine: 1) the percentage of the population with intakes greater than the Adequate Intakes (AI) for calcium and potassium and the percentage of the population with inadequate magnesium intake (based on Estimated Average Requirement [EAR]) and 2) the impact of various levels of dairy consumption on intake of calcium, potassium and magnesium.Design: Secondary analysis of data from the 1999-2004 NHANES.Subjects/Setting: Participants 2 years of age and older.Main Outcome Measures: Percentage of the population meeting current recommendations for calcium, potassium and magnesium.Statistical Analyses Performed: Percentage of EAR/AI for nutrients was calculated based on age/gender specific values. All analyses were weighted using the NHANES six-year sample weights and adjusted for the complex sample design of NHANES with the statistical package SUDAAN.Results: The most recent NHANES data demonstrated that a significant proportion of the American population did not meet recommendations for calcium, potassium, and magnesium. Less than 3% of the population consumed the recommended level or more of potassium. Only 30% of the US population 2 years of age and older obtained the recommended level of calcium or more and 55% consumed less than the EAR for magnesium. Recommending 3–4 servings from the dairy group for all people greater than 9 years of age may be necessary in order to ensure adequate intake of calcium and magnesium, assuming the current diet remains the same. More than 4 servings of dairy would be needed to meet the potassium recommendation at all ages.Conclusions: For those individuals who do not consume dairy products, we need to better understand the barriers to consuming specific dairy products. In addition, more research is needed to examine whether food-based recommendations are practical, feasible and cost effective to meet nutrient needs.

The Need for Time-Intensive Information in Healthful Eating and Physical Activity Research: A Timely Topic

Unhealthful dietary practices and physical inactivity are associated with the leading causes of mortality in the United States ( 1 Mokdad A.H. Marks J.S. Stroup D.F. Gerberding J.L. Correction: Actual causes of death in the United States, 2000. JAMA. 2005; 293: 293-294 Google Scholar , 2 Mokdad A.H. Marks J.S. Stroup D.F. Gerberding J.L. Actual causes of death in the United States, 2000. JAMA. 2004; 291: 1238-1245 Google Scholar ). Despite well-established linkages between poor nutritional habits and sedentary behavior and a host of chronic and serious diseases, such as diabetes, heart disease, and cancer ( 3 Dietary Guidelines Advisory CommitteeThe Report of the Dietary Guidelines Advisory Committee on Dietary Guidelines for Americans, 2005. US Department of Health and Human Services, US Department of Agriculture, Washington, DC2005 Google Scholar , 4 Physical Activity Guidelines Advisory CommitteePhysical Activity Guidelines Advisory Committee Report, 2008. US Department of Health and Human Services, Washington, DC2008 Google Scholar , 5 US Department of Health and Human ServicesPhysical Activity and Health: A Report of the Surgeon General. US Department of Health and Human Services, Atlanta, GA1996 Google Scholar ), many Americans do not meet minimum daily recommendations for the intake of essential nutrients and physical activity. Recent estimates suggest <50% of US adults engage in regular physical activity based on self-reported information ( 6 National Center for Health StatisticsHealth, United States, 2007 with Chartbook on Trends in the Health of Americans. National Center for Health Statistics, Hyattsville, MD2007 Google Scholar ). Also, only 32.6% of adults reportedly consume fruit two or more times per day and 27.2% eat vegetables three or more times per day ( 7 Centers for Disease Control and PreventionFruit and vegetable consumption among adults—United States, 2005. MMWR Morb Mortal Wkly Rep. 2007; 56: 213-217 Google Scholar ). To address this public health crisis, there is an urgent need to elucidate key processes underlying healthful lifestyle decisions and develop strategies to promote healthful eating and physical activity. This commentary describes how acquiring time-intensive information about microcontextual and intraindividual factors influencing daily and within-daily dietary and activity decisions is a critical step to accomplishing this goal. G. Fridlund Dunton is a cancer prevention fellow, Health Promotion Research Branch, Behavioral Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD. A. A. Atienza is program director in the Health Promotion Research Branch, Behavioral Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD.

Food rating systems, diet quality, and health

The issue of nutrient density is not new. Almost 30 years ago, researchers described ways to measure a “nutritious” food.1 Indeed, the first regulation to set standards for items sold in competition with school meals in the 1980s was based on a nutrient density approach. However, there has been a renewed emphasis on nutrient density as a way to rate foods and as a way to promote more healthful eating in the general population. This has partly been sparked by the 2005 Dietary Guidelines for Americans.2 For example, “get the most nutrients out of your calories” and “make smart choices for every good group” are statements that come directly out of the Dietary Guidelines Advisory Committee report.2 Unfortunately, nutrient density is not a concept that is clearly understood by the consumer. Thus, the article by Drewnowski and Fulgoni in this issue is relevant and timely.3 In recent years there has been a proliferation of …

Revised dietary guidelines for Koreans.

With rapidly changing dietary environment, dietary guidelines for Koreans were revised and relevant action guides were developed. First, the Dietary Guidelines Advisory Committee was established with experts and government officials from the fields of nutrition, preventive medicine, health promotion, agriculture, education and environment. The Committee set dietary goals for Koreans aiming for a better nutrition state of all after a thorough review and analysis of recent information related to nutritional status and/or problems of Korean population, changes in food production/supply, disease pattern, health policy and agricultural policy. Then, the revised dietary guidelines were proposed to accomplish these goals in addition to 6 different sets of dietary action guides to accommodate specific nutrition and health problems of respective age groups. Subsequently, these guidelines and guides were subjected to the focus group review, consumer perception surveys, and a public hearing for general and professional comments. Lastly, the language was clarified in terms of public understanding and phraseology. The revised Dietary guidelines for Koreans are as follows: eat a variety of grains, vegetables, fruits, fish, meat, poultry and dairy products; choose salt-preserved foods less, and use less salt when you prepare foods; increase physical activity for a healthy weight, and balance what you eat with your activity; enjoy every meal, and do not skip breakfast; if you drink alcoholic beverages, do so in moderation; prepare foods properly, and order sensible amounts; enjoy our rice-based diet.

Iron Intake in Relation to Diet and Iron Status of Young Adult Women

Aims: To determine the iron intake and food sources of iron in young adult women and to compare women with high versus low iron intake on diet and iron status. Methods: Iron intake and food sources were assessed by a 2-day estimated food record. Iron status was determined by a fasting venous blood sample. Differences in diet and iron status between women with high versus low iron intake were examined by comparing women of the fourth respectively first quartile of total iron intake (mg/day). Results: The median total, heme and non-heme iron intake was 10.6, 0.6 and 9.8 mg/day, respectively. The median iron intake was 93 and 131% of the estimated average requirement (EAR) of the UK (11.4 mg/day) and USA (8.1 mg/day), respectively. The most important iron intake contributors were cereals and cereal products (31%), meat and meat products (12%) and vegetables (10%). Women with a high iron intake showed a significantly higher energy-adjusted intake of alcoholic beverages and soups and a lower intake of non-alcoholic beverages than women with a low iron intake. Approximately 5% of the women had anemia, of which 3% had iron deficiency anemia (IDA). Almost 20% was iron-deficient non-anemic. In this regard, no significant differences were found between the iron intake quartiles. Conclusion: The median iron intake in this study population is considerably below the national recommended dietary allowance (20 mg/day). However, based on the approach of the Dietary Guidelines Advisory Committee, iron intake seems to pose no major health problem when using the EAR as a reference. The number of women with IDA was indeed not alarming (3%), although 20% was iron-deficient non-anemic. The question remains whether an increase in iron intake can improve iron status.

An evidence-based approach for establishing dietary guidelines.

Although all agree that diet is important to health, for Americans, compliance with dietary guidelines is poor. This may be because socioeconomic, cultural, and political factors influencing food habits were given little consideration when the guidelines were derived. In 2005, the Dietary Guidelines Advisory Committee was advised to focus their analysis on scientific evidence linking diet and health. Although this approach strengthened the scientific rationale behind the guidelines, factors from the "real world" affecting compliance received little attention. The research base for the guidelines needs to be expanded to include studies of barriers to compliance as well as randomized controlled trials of whole diets. Also, the process for formulating the guidelines needs to be expanded to include input from the diverse group of users and stakeholders. Possibly, a 3-step process involving a technical analysis, user appraisal, and federal formulation, all coordinated by a Standing Dietary Guidelines Committee, would broaden assessment of relevant data and better integrate conflicting uses and applications.

MyPyramid Food Intake Pattern Modeling for the Dietary Guidelines Advisory Committee

Modeling analyses using the MyPyramid intake patterns were conducted in collaboration with the 2005 Dietary Guidelines Advisory Committee in response to their research questions and to determine likely effects of possible recommendations on overall dietary adequacy. Scenarios modeled included the feasibility of using the food patterns for lacto-ovo-vegetarian diets, of varying fat levels within the patterns, and of increasing dietary flexibility through food group substitutions. Food pattern modeling was a useful tool to identify possible impacts on diet quality of potential Dietary Guidelines recommendations. Modeling analyses can help researchers explore the overall effect of specific dietary recommendations on intake patterns.

The 2005 Dietary Guidelines Advisory Committee Report

The 2005 Dietary Guidelines Advisory Committee Report

The 2005 Dietary Guidelines Advisory Committee: Developing a Key Message

The 2005 Dietary Guidelines Advisory Committee used an evidence-based approach to evaluate the science base for the relationships of diet and physical activity and health. Nine key messages and corresponding conclusions were included in the 2005 Dietary Guidelines Advisory Committee report. This article describes the development process, scientific basis, and specific recommendations for one of the key messages.

Dietary Guidelines 2005—Contributions of Registered Dietitians to the Evolution and Dissemination of the Guidelines

K A T w r u m f O a f l a r n he 2005 Dietary Guidelines Advisory Committee report used an evidence-based approach to develop nine key messages on the following topics: adequate utrients within calorie needs, weight management, hysical activity, food groups to encourage, fats, carbohyrates, sodium and potassium, alcoholic beverages, and ood safety (1). These topics were the basis for the 41 “key ecommendations” in the Dietary Guidelines for Amerians 2005, of which 23 are for the general public and 18 re targeted to specific population groups. Collectively, he 2005 Dietary Guidelines (2) are intended to promote healthful eating pattern, achieve and maintain a ealthy body weight, and encourage a program of regular hysical activity for the purposes of promoting health, ecreasing risk of chronic diseases, and achieving optimal rowth and development. Taken together the messages onveyed in the 2005 Dietary Guidelines are intended to e implemented as a “total package.” Simply stated, the 005 Dietary Guidelines encourage Americans to conume fewer calories, be more active, and make prudent ood choices—the goal being to meet all nutrient needs nd other dietary recommendations without exceeding nergy requirements. The process followed by the Dietary uidelines Advisory Committee is discussed by Nicklas nd colleagues (3) in this issue of the Journal as it relates o the first key message (ie, adequate nutrients within alorie needs). The purpose of this Commentary is to iscuss the seminal role that registered dietitians played n the development of the 2005 Dietary Guidelines, and to ncourage their leadership and participation in dissemi-

The 2005 Dietary Guidelines Advisory Committee Report

In Brief The 2005 Dietary Guidelines Advisory Committee evaluated the science base for the relationships of diet and physical activity and health using an evidence-based approach. The USDA Food Intake Patterns were used as a tool to model food group recommendations that meet 100% of the current Dietary Reference Intake standards for most nutrients. Americans need to make substantial changes in food choices to meet their nutrient needs without exceeding their energy needs. The new guidelines stress the importance of making calories count by choosing nutrient-dense foods combined with adequate physical activity. An insider's look into the 2005 Dietary Guidelines Report