Understanding the Bigger Picture of Dietary Guidelines

The first US dietary recommendations were set by the National Academy of Sciences in 1941. The (RDA) were first established out of concern that America’s overseas World War II troops were not consuming enough daily nutrients to maintain good health. The first Food and Nutrition Board was created in 1941, and in the same year set recommendations for the adequate intakes of caloric energy and eight essential nutrients. These were disseminated to officials responsible for food relief for armed forces and civilians supporting the war effort. Since 1980, the dietary guidelines have been reevaluated and updated every five years by the advisory committees of the US Department of Agriculture (USDA) and the US Department of Health and Human Services (HHS). The guidelines are continually revised to keep up with new scientific evidence-based conclusions on the importance of nutritional adequacy and physical activity to overall health.

While dietary recommendations set prior to 1980 focused only on preventing inadequacy, the current dietary guidelines have the additional goals of promoting health, reducing chronic disease, and decreasing the prevalence of overweight and obesity.

Establishing Human Nutrient Requirements for Worldwide Application

The Department of Nutrition for Health and Development, in collaboration with FAO, continually reviews new research and information from around the world on human nutrient requirements and recommended nutrient intakes. This is a vast and never-ending task, given the large number of essential human nutrients. These nutrients include protein, energy, , fats and , a range of vitamins, and a host of and trace elements.

Many countries rely on WHO and FAO to establish and disseminate this information, which they adopt as part of their national dietary allowances. Others use it as a base for their standards. The establishment of human nutrient requirements is the common foundation for all countries to develop food-based dietary guidelines for their populations.

Establishing requirements means that the public health and clinical significance of intake levels – both deficiency and excess – and associated disease patterns for each nutrient, need to be thoroughly reviewed for all age groups. Every ten to fifteen years, enough research is completed and new evidence accumulated to warrant WHO and FAO undertaking a revision of at least the major nutrient requirements and recommended intakes[1].

Why Are Guidelines Needed?

Instituting nation-wide standard policies provides consistency across organizations and allows health-care workers, nutrition educators, school boards, and eldercare facilities to improve nutrition and subsequently the health of their respective populations. At the same time, the goal of the Dietary Guidelines is to provide informative guidelines that will help any interested person in obtaining optimal nutritional balance and health. These guidelines are from the review of thousands of scientific journal articles by a consensus panel consisting of more than two thousand nutrition experts with the overall mission of improving the health of the nation[2].


The Dietary Guidelines are published and revised every five years jointly by the U.S. Department of Agriculture (USDA) and Health and Human Services (HHS) as a guide to healthy eating for Americans. [3] 


The purpose of the Dietary Guidelines is to give Americans evidence-based information on what to eat and drink to promote health and prevent chronic disease. Public health agencies, health care providers, and educational institutions all rely on Dietary Guidelines recommendations and strategies.[4] These agencies use the Dietary Guidelines to:

  • Form the basis of federal nutrition policy and programs such as WIC and SNAP
  • Help guide local, state, and national health promotion and disease prevention initiatives
  • Inform various organizations and industries (for example, products developed and marketed by the food and beverage industry)


Before HHS and the USDA release the new Dietary Guidelines, they assemble an Advisory Committee. This committee is composed of nationally recognized nutrition and medical researchers, academics, and practitioners. The Advisory Committee develops an Advisory Report that synthesizes current scientific and medical evidence in nutrition, which will then advise the federal government in the development of the new edition of the Dietary Guidelines.

The public also has opportunities to get involved in the development of these guidelines. The Advisory Committee holds a series of public meetings for hearing oral comments from the public, and the public also has opportunities to provide written comments to the Advisory Committee throughout the course of its work. After the Advisory Report is complete, the public has opportunities to respond with written comments and provide oral testimony at a public meeting.

2020-2025 Dietary Guidelines

The major topic areas of the Dietary Guidelines are:

  1. Follow a healthy dietary pattern at every life stage.
  2. Customize and enjoy nutrient-dense food and beverage choices to reflect personal preferences, cultural traditions, and budgetary considerations.
  3. Focus on meeting food group needs with nutrient-dense foods and beverages, and stay within calorie limits.
  4. Limit foods and beverages higher in added sugars, saturated fat, and sodium, and limit alcoholic beverages.


Green bunch of tangerines in woven basket.
Image by Jim Hollyer / CC BY 4.0

Several nutrients are of special public health concern, including dietary fiber, calcium, potassium, and vitamin D. Inadequate intake of these nutrients is common among Americans and is associated with greater risk of chronic disease. People can increase their intake of these nutrients by shifting towards eating more vegetables, fruits, whole grains, dairy products, and beans. The Dietary Guidelines thus encourage the following nutrient-dense food choices:


  • Vegetables, including a variety of dark green, red and orange, legumes (beans and peas), starchy and other vegetables
  • Fruits, especially whole fruits
  • Grains, at least half of which are whole grains
  • Dairy, including fat-free or low-fat milk, yogurt, and cheese, and/or fortified soy beverages and yogurt
  • Protein foods, including seafood (8 or more ounces per week), lean meats and poultry, eggs, legumes (beans, peas, lentils), soy products, and nuts and seeds
  • Oils, including those from plants, such as canola, corn, olive, peanut, safflower, soybean, and sunflower oils, and those present in whole foods such as nuts, seeds, seafood, olives, and avocados.


The Dietary Guidelines explains that most of an individual’s daily caloric intake—about 85%—must be made up of nutrient-dense foods in order to meet nutrient requirements, leaving about 15% of calories available for other uses. Yet many Americans consume too much of foods with added sugars and saturated fat, in addition to excessive amounts of sodium and alcohol. Consuming too much of these dietary components is associated with development of chronic disease over time and can add calories without providing much in the way of beneficial nutrients. Therefore, the Dietary Guidelines recommends limiting the following:


  • Added sugars – Consume less than 10 percent of calories per day from added sugars starting at age 2. (Avoid foods and beverages with added sugars for those younger than age 2.)
  • Saturated fat – Consume less than 10 percent of calories per day from saturated fat starting at age 2.
  • Sodium – Consume less than 2,300 milligrams (mg) per day of sodium – and even less for children younger than age 14.
  • Alcoholic beverages – If alcohol is consumed, it should be consumed only in moderation (up to one drink per day for women and up to two drinks per day for men). Drinking less is better for health than drinking more.

Learning Activities

Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities.  These activities are available in the web-based textbook and not available in the downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document).

Learning activities may be used across various mobile devices, however, for the best user experience it is strongly recommended that users complete these activities using a desktop or laptop computer.



  1. http://www.who.int/nutrition/topics/nutrecomm/en/
  2. Johnson TD. (2011). New Dietary Guidelines Call for Less Salt, Fewer Calories, More Exercise. Nation’s Health, 41(2), E6. http://thenationshealth.aphapublications.org/content/41/2/E6.full. Accessed November 22, 2017. Key Recommendations: Components of Healthy Living Patterns. Dietary Guidelines 2015-2020. https://health.gov/dietaryguidelines/2015/guidelines/chapter-1/key-recommendations/. Published 2015. Accessed November 22, 2017.
  3. Office of Disease Prevention and Health Promotion. (2020). About the Dietary Guidelines. Retrieved from  https://health.gov/our-work/food-nutrition/about-dietary-guidelines
  4. Office of Disease Prevention and Health Promotion. (2020). About the Dietary Guidelines. Retrieved from  https://health.gov/our-work/food-nutrition/about-dietary-guidelines


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