Updated nutritional guidelines emphasize holistic eating patterns over the course of a lifespan.
The Guidelines are based largely on the recommendations from the Dietary Guidelines Advisory Committee (Advisory Committee), which is comprised of expert researchers in the fields of nutrition, health, and medicine. The HHS and USDA stated that the updated Guidelines are intended to “reduce obesity and prevent chronic diseases like Type 2 diabetes, hypertension, and heart disease.” Importantly, the Guidelines emphasize healthy eating patterns to increase population health, rather than focusing on individual nutrients or foods. The Guidelines state that Americans should focus on maintaining healthy body weight through nutrient adequacy over their lifespan. Reading between the lines, the Guidelines seem to advocate that Americans should avoid so-called “fad diets” that can lead to “yo-yo” weight fluctuations.
The Guidelines’ Recommendations for a Healthy Diet
The Guidelines are based on systematic reviews of scientific research, food pattern modeling, and analyses of current food intake of the US population as evaluated by the Advisory Committee.
According to the Guidelines, scientific evidence has shown that the following have consistently been identified with healthy eating patterns:
- Higher intakes of vegetables and fruits
- Lower intakes of meats, including processed meats, sugar-sweetened foods and beverages, and refined grains
The following have been identified with healthy eating patterns with less consistency:
- Whole grains
- Fat-free or low-fat dairy
The Guidelines outline five main principles for a healthy eating pattern:
- Follow a healthy eating pattern across an entire lifespan—an eating pattern is the combination of food and drink that a person eats over time
- Focus on variety, nutrient-dense foods, and amount of intake
- Limit calories from added sugars and saturated fats, and reduce sodium intake
- Shift to healthier food and beverage choices
- Support healthy eating for all
While the Guidelines recommend a holistic approach to nutrition, they also address specific nutrients such as added sugars, sodium, saturated fats, cholesterol, and caffeine. Generally, Americans should limit daily calorie intake in the following ways:
- Less than 10% of calories should come from added sugars
- Less than 10% of calories should come from saturated fats
- Less than 2,300 mg of sodium should be consumed per day
- Alcohol intake should be limited to one drink per day for women and two drinks per day for men
The Guidelines note that the limits on calories from added sugars and saturated fats are not Tolerable Upper Intake Levels (ULs) as set by the Institute of Medicine (IOM). A UL is “the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects to almost all individuals in the general population.” For most calorie levels, there are not enough calories available after meeting food group needs to consume 10% of calories from added sugars and 10% of calories from saturated fats and still stay within calorie limits. In other words, the Guidelines do not recommend that individuals consume 10% of calories from saturated fat and added sugars, but rather recommend limiting the consumption of these nutrients to a maximum of 10% of caloric intake. Additionally, the Guidelines note that they do not recommend individuals begin to consume alcohol, rather, they should limit consumption of alcohol. Finally, the Guidelines do not establish a recommended amount of consumption for caffeine. The Guidelines state that moderate caffeine consumption is not associated with an increased risk of major chronic diseases, and therefore, can be incorporated into a healthy eating pattern. However, the Guidelines caution mixing caffeine and alcohol, and note that the Guidelines are not recommending the addition of caffeine to a diet that does not currently include it.
The Guidelines recommend limiting the intake of trans fats and cholesterol to a minimum. The cholesterol recommendation in the updated Guidelines represents a change from the 2010 Guidelines, which recommended limiting cholesterol to 300 mg per day; studies since 2010 have shown that limiting cholesterol to a minimum is associated with reduced risk of cardiovascular disease and obesity. Accordingly, because more research is needed to establish a quantitative limit for a cholesterol level, the updated Guidelines recommend limiting intake of cholesterol to the minimal amount possible for the individual.
Regarding sodium, the IOM, American Heart Association, and Dietary Guidelines Advisory Committees state that the current average American sodium intake of 3,440 mg is too high, and recommends consumption be reduced to a maximum of 2,300 mg per day for adults and children ages 14 and older. Sodium intake should be even further lowered for individuals with hypertension. Individuals with hypertension may consider the Dietary Approaches to Stop Hypertension (DASH) dietary pattern, as described in the Guidelines. The DASH dietary pattern was designed to lower blood pressure and LDL cholesterol by lowering sodium intakes to 1,500 mg per day. DASH has been shown to be effective when compared to the typical American diet. The DASH dietary pattern is high in vegetables, fruits, low-fat dairy products, whole grains, poultry, fish, beans, and nuts, and is low in sweets, sugar-sweetened beverages, and red meats.
Notably, the Guidelines include two new USDA Food Patterns: the Healthy Mediterranean-Style Eating Pattern and the Healthy Vegetarian Eating Pattern. The Guidelines state that the addition of these two eating patterns reflects different styles and cultural preferences.
Advisory Committee Recommendations Excluded from the Guidelines
While the Guidelines are based on the recommendations from the Advisory Committee, some of the Committee’s recommendations were not included in the final Guidelines. For example, the “Food Sustainability and Safety” section of the Advisory Committee’s recommendations is absent. The Advisory Committee defined a “sustainable diet” as “a pattern of eating that promotes health and well-being and provides food security for the present population while sustaining human and natural resources for future generations.” While the Guidelines address and discuss the “Social Ecological Model” of how individuals make food and physical activity choices, this model does not specifically address sustainability.
Additionally, the Advisory Committee recommended a reduction in the consumption of red and processed meat; however, this recommendation was not included in the final Guidelines. The Guidelines include a recommendation for the inclusion of “lean meat” as a protein, which was assessed by the Advisory Committee as part of a healthy diet. While the Guidelines state that “eating patterns that include lower intake of meats as well as processed meats and processed poultry are associated with reduced risk of [cardiovascular disease] in adults,” and that “average intakes of meats, poultry, and eggs for teen boys and adult men are above recommendations in the Healthy US-Style Eating Pattern,” it does not explicitly recommend a lowered consumption of red and processed meat. The Guidelines state that healthy eating patterns “may include processed meats and processed poultry as long as the resulting eating pattern is within limits for sodium, calories from saturated fats and added sugars, and total calories.”
Overall, according to the HHS and the USDA, the 2015-2020 Dietary Guidelines for Americans are based on scientific assessments and reflect cultural and personal preferences with regard to diets. The Guidelines’ major focus is on healthy and nutrient-dense eating patterns over time, while avoiding certain nutrients known to have harmful effects in large quantities. It is the hope of the HHS and USDA that this holistic approach will reduce obesity and help prevent Type 2 diabetes, hypertension, and heart disease in the American population.