In 1980, the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (HHS) released the first edition of Nutrition and Your Health: Dietary Guidelines for Americans. These Dietary Guidelines were different from previous dietary guidance in that they reflected emerging scientific evidence about diet and health and expanded the traditional focus on nutrient adequacy to also address the impact of diet on chronic disease.

Subsequent editions of the Dietary Guidelines for Americans have been remarkably consistent in their recommendations about the components of a health-promoting diet, but they also have changed in some significant ways to reflect an evolving body of evidence about nutrition, the food and physical activity environment, and health. The ultimate goal of the Dietary Guidelines for Americans is to improve the health of our Nation’s current and future generations by facilitating and promoting healthy eating and physical activity choices so that these behaviors become the norm among all individuals.

The recommendations contained in the Dietary Guidelines for Americans traditionally have been intended for healthy Americans ages 2 years and older. However, Dietary Guidelines for Americans, 2010 is being released at a time of rising concern about the health of the American population. Its recommendations accommodate the reality that a large percentage of Americans are overweight or obese and/or at risk of various chronic diseases. Therefore, the Dietary Guidelines for Americans, 2010 is intended for Americans ages 2 years and older, including those who are at increased risk of chronic disease.

Poor diet and physical inactivity are the most important factors contributing to an epidemic of overweight and obesity in this country. The most recent data indicate that 72 percent of men and 64 percent of women are overweight or obese, with about one-third of adults being obese.^[1] Even in the absence of overweight, poor diet and physical inactivity are associated with major causes of morbidity and mortality. These include cardiovascular disease, hypertension, type 2 diabetes, osteoporosis, and some types of cancer. Some racial and ethnic population groups are disproportionately affected by the high rates of overweight, obesity, and associated chronic diseases. These diet and health associations make a focus on improved nutrition and physical activity choices ever more urgent. These associations also provide important opportunities to reduce health disparities through dietary and physical activity changes.

Dietary Guidelines for Americans also recognizes that in recent years nearly 15 percent of American households have been unable to acquire adequate food to meet their needs because of insufficient money or other resources for food.^[2] This dietary guidance can help them maximize the nutritional content of their meals within their resource constraints. Many other Americans consume less than optimal intake of certain nutrients, even though they have adequate resources for a healthy diet. This dietary guidance and nutrition information can help them choose a healthy, nutritionally adequate diet.

Children are a particularly important focus of the Dietary Guidelines for Americans because of the growing body of evidence documenting the vital role that optimal nutrition plays throughout the lifespan. Today, too many children are consuming diets with too many calories and not enough nutrients and are not getting enough physical activity. Approximately 32 percent of children and adolescents ages 2 to 19 years are overweight or obese, with 17 percent of children being obese.^[3] In addition, risk factors for adult chronic diseases are increasingly found in younger ages. Eating patterns established in childhood often track into later life, making early intervention on adopting healthy nutrition and physical activity behaviors a priority.

Developing the Dietary Guidelines for Americans, 2010

Because of their focus on health promotion and disease risk reduction, the Dietary Guidelines form the basis for nutrition policy in Federal food, education, and information programs. By law (Public Law 101-445, Title III, 7 U.S.C. 5301 et seq.), the Dietary Guidelines for Americans is reviewed, updated if necessary, and published every 5 years. The process to create each edition of the Dietary Guidelines for Americans is a joint effort of the USDA and HHS and has evolved to include three stages.

In the first stage, an external scientific Dietary Guidelines Advisory Committee (DGAC) is appointed to conduct an analysis of new scientific information on diet and health and to prepare a report summarizing its findings. The Committee’s analysis is the primary resource for the two Departments in developing the Dietary Guidelines for Americans. The 2010 DGAC used a systematic evidence-based review methodology involving a web-based electronic system to facilitate its review of the scientific literature and address approximately 130 scientific questions. The methodological rigor of each study included in the analysis was assessed, and the body of evidence supporting each question was summarized, synthesized, and graded by the Committee (this work is publicly available at http://www.nutritionevidencelibrary.gov). The DGAC used data analyses, food pattern modeling analyses,^[4] and reviews of other evidence-based reports to address an additional 50 questions.

The DGAC report presents a thorough review of key nutrition, physical activity, and health issues, including those related to energy balance and weight management; nutrient adequacy; fatty acids and cholesterol; protein; carbohydrates; sodium, potassium, and water; alcohol; and food safety and technology. Following its completion in June 2010, the DGAC report was made available to the public and Federal agencies for comment. For more information about the process and the Committee’s review, see the Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans, 2010 at http://www.dietaryguidelines.gov.

During the second stage, the Departments develop the policy document, Dietary Guidelines for Americans. The audiences for this document include policymakers, nutrition educators, nutritionists, and healthcare providers. Similar to previous editions, the 2010 edition of Dietary Guidelines for Americans is based on the Advisory Committee’s report and a consideration of public and Federal agency comments. The Dietary Guidelines science-based recommendations are used for program and policy development. In the third and final stage, the two Departments develop messages and materials communicating the Dietary Guidelines to the general public.

A RoadMap to the Dietary Guidelines For Americans, 2010

Dietary Guidelines for Americans, 2010 consists of five pages in this chapter. This first page introduces the document and provides information on background and purpose. The next four pages correspond to major themes that emerged from the 2010 DGAC’s review of the evidence, with recommendations with supporting evidence and explanations. These recommendations are based on a preponderance of the scientific evidence for nutritional factors that are important for promoting health and lowering risk of diet-related chronic disease. Quantitative recommendations always refer to individual intake or amount rather than population average intake, unless otherwise noted.

Although divided into pages that focus on particular aspects of eating patterns, Dietary Guidelines for Americans provides integrated recommendations for health. To get the full benefit, individuals should carry out these recommendations in their entirety as part of an overall healthy eating pattern:

• Balancing Calories to Manage Weight explains the concept of calorie balance, describes some of the environmental factors that have contributed to the current epidemic of overweight and obesity, and discusses diet and physical activity principles that can be used to help Americans achieve calorie balance.
• Foods and Food Components to Reduce focuses on several dietary components that Americans generally consume in excess compared to recommendations. These include sodium, solid fats (major sources of saturated fats and trans fats), cholesterol, added sugars, refined grains, and for some Americans, alcohol. The chapter explains that reducing foods and beverages that contain relatively high amounts of these dietary components and replacing them with foods and beverages that provide substantial amounts of nutrients and relatively few calories would improve the health of Americans.
• Foods and Nutrients to Increase focuses on the nutritious foods that are recommended for nutrient adequacy, disease prevention, and overall good health. These include vegetables; fruits; whole grains; fat-free or low-fat milk and milk products;^[14] protein foods, including seafood, lean meat and poultry, eggs, beans and peas, soy products, and unsalted nuts and seeds; and oils. Additionally, nutrients of public health concern, including potassium, dietary fiber, calcium, and vitamin D, are discussed.
• Building Healthy Eating Patterns shows how the recommendations and principles described in earlier chapters can be combined into a healthy overall eating pattern. The USDA Food Patterns and DASH Eating Plan are healthy eating patterns that provide flexible templates allowing all Americans to stay within their calorie limits, meet their nutrient needs, and reduce chronic disease risk.

Sources of Information

For more information about the articles and reports used to inform the development of the Dietary Guidelines for Americans, readers are directed to the Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans, 2010 and the related Nutrition Evidence Library website (http://www.nutritionevidencelibrary.gov). Unless otherwise noted, usual nutrient, food group, and selected dietary component intakes by Americans are drawn from analyses conducted by the National Cancer Institute (NCI),^[15] a component of HHS’s National Institutes of Health, and by USDA’s Agricultural Research Service (ARS),^[16] using standard methodologies and data from the National Health and Nutrition Examination Survey (NHANES). Additional references are provided throughout this document, where appropriate.

Importance of the Dietary Guidelines for Health Promotion and Disease Prevention

A growing body of scientific evidence demonstrates that the dietary and physical activity recommendations described in the Dietary Guidelines for Americans may help people attain and maintain a healthy weight, reduce the risk of chronic disease, and promote overall health. These recommendations accommodate the varied food preferences, cultural traditions, and customs of the many and diverse groups who live in the United States.

A basic premise of the Dietary Guidelines is that nutrient needs should be met primarily through consuming foods. Foods provide an array of nutrients and other components that are thought to have beneficial effects on health. Americans should aim to consume a diet that achieves the Institute of Medicine’s most recent Dietary Reference Intakes (DRIs), which consider the individual’s life stage, gender, and activity level. In some cases, fortified foods and dietary supplements may be useful in providing one or more nutrients that otherwise may be consumed in less than recommended amounts. Another important premise of the Dietary Guidelines is that foods should be prepared and handled in a way that reduces risk of foodborne illness. All of these issues are discussed in detail in the remainder of this document and its appendices.

Uses of the Dietary Guidelines for Americans, 2010

As with previous editions, Dietary Guidelines for Americans, 2010 forms the basis for nutrition policy in Federal food, nutrition, education, and information programs. This policy document has several specific uses.

Development of Educational Materials and Communications

The information in this edition of Dietary Guidelines for Americans is used in developing nutrition education and communication messages and materials. For example, Federal dietary guidance publications are required by law to be consistent with the Dietary Guidelines.

When appropriate, specific statements in Dietary Guidelines for Americans, 2010 indicate the strength of the evidence (e.g., strong, moderate, or limited) related to the topic as summarized by the 2010 Dietary Guidelines Advisory Committee. The strength of evidence is provided so that users are informed about how much evidence is available and how consistent the evidence is for a particular statement or recommendation. This information is useful for educators when developing programs and tools. Statements supported by strong or moderate evidence can and should be emphasized in educational materials over those with limited evidence.

When considering the evidence that supports a recommendation, it is important to recognize the difference between association and causation. Two factors may be associated; however, this association does not mean that one factor necessarily causes the other. Often, several different factors may contribute to an outcome. In some cases, scientific conclusions are based on relationships or associations because studies examining cause and effect are not available. When developing education materials, the relationship of associated factors should be carefully worded so that causation is not suggested.

Development of Nutrition-Related Programs

The Dietary Guidelines aid policymakers in designing and implementing nutrition-related programs. For example, the Federal Government uses the Dietary Guidelines in developing nutrition assistance programs such as the National Child Nutrition Programs and the Elderly Nutrition Program. The Dietary Guidelines also provide the foundation for the Healthy People national health promotion and disease prevention objectives related to nutrition, which set measurable targets for achievement over a decade.

Development of Authoritative Statements

The Dietary Guidelines for Americans, 2010 has the potential to offer authoritative statements as a basis for health and nutrient content claims, as provided for in the Food and Drug Administration Modernization Act (FDAMA). Potential authoritative statements should be phrased in a manner that enables consumers to understand the claim in the context of the total daily diet. FDAMA upholds the “significant scientific agreement” standard for authorized health claims. By law, this standard is based on the totality of publicly available scientific evidence. Therefore, for FDAMA purposes, statements based on, for example, evidence that is moderate, limited, inconsistent, emerging, or growing, are not authoritative statements.