The DGAC findings can be valuable to food marketers in gaining an understanding of the scientific literature underscoring various diet and health relationships. In some cases, the DGAC Scientific Advisory Report (and underlying science) can be a good way to develop claim substantiation. Accordingly, a careful review of the findings in areas of specific interest is recommended. The strengths and limitations of the relevant findings should also be considered in framing nutrition and health claim benefits. To this end, we have found the scientific summaries and references useful in assisting in the development of nutrition and health benefit claims. Stakeholders are also given an opportunity to submit comments3.
Current Dietary Intakes
As background, the DGAC states that more than 70% of Americans are overweight or obese, with 6 in 10 Americans having at least one chronic disease, and 4 in 10 Americans having at least two chronic diseases. The report found that across the lifespan, the typical American diet results in overconsumption of total energy (calories), saturated fats, sodium, added sugars, and, for some individuals, alcoholic beverages. For Americans aged 1 year and older, current data suggest that under consumption of Vitamin D, calcium, dietary fiber, and potassium are a public health concern. Planned dietary recommendations for infants and toddlers, and pregnant women prompted a review of intake patterns for these populations for the first time. A continued and deeper focus on dietary patterns (versus individual foods and nutrients) and specific health are also included.
Recommendations to Reduce Added Sugars Consumption
DGAC is recommending that Americans consume less than 6% of total energy from added sugars, down from the 10% of total energy recommended in the 2015-2020 Dietary Guidelines for Americans. Based on a 2,000 calorie diet, 6% of total energy from added sugars would equal 30 g added sugars. DGAC explains that while added sugar consumption has gone down slightly, reducing the amount of added sugar in the diet – either through changes in consumer behavior or how food is produced and sold – would improve population health. According to the report, nearly 70% or more of added sugar intake across all age-sex groups are contributed by 5 food categories: (1) sweetened beverages (i.e., soft drinks, fruit drinks, sports and energy drinks, including smoothies and grain drinks), (2) desserts and sweet snacks; (3) coffee and tea (with their additions); (4) candy and sugars (e.g., jams, syrups, toppings), and (5) breakfast cereals and bars. With respect to sweetened beverages (excluding coffee and tea with added sugar), the report found that these account for approximately 1/3 of total beverage consumption, and approximately 30%, 50%, and 60% of added sugars in the diet of young children, adolescents, and adults, respectively.
Frequency of Eating and Snacking
For the first time, the DGAC is directly addressing the frequency of eating in addition to the types and amounts of food ingested. Highlights of the findings on the frequency of eating in the report include:
On average, Americans report 5.7 eating occasions per day, with most people consuming 3 meals (64%) or 2 meals (28%) per day.
When compared with 2 meals, Americans who eat 3 meals per day tend to have 5-point higher Healthy Eating Index scores.
Insufficient evidence was available for the DGAC to determine the relationship between frequency of eating and growth, size, body composition, risk of being overweight or obesity, all-cause mortality, or risk of type 2 diabetes.
Of particular focus in the frequency of eating discussion is the role of snacking. The DGAC’s report suggests following a dietary pattern that reduces snacking and emphasizes meals, and ensures that both snacks and meals are primarily comprised of foods and beverages that contribute to nutrient and food group recommendations, to help align eating patterns with dietary guideline recommendations. The DGAC found that 93% of Americans snack daily, and on average, snack 2-3 times per day, with snacks accounting for 22-23% of total calories consumed. Increasing public awareness and research activity related to certain aspects of eating frequency, such as “grazing,” intermittent fasting, meal skipping, and late-night eating are also noted in the report.
Recommendations on Dietary Fats and Seafood
The DGAC report found that reducing saturated fat intake by replacing it with unsaturated fats lowers the incidence of cardiovascular disease in adults, and reduces serum total and low-density lipoprotein cholesterol in all adults and some children, especially boys. DGAC emphasizes that the shift from saturated to unsaturated fats best occurs in a healthy dietary pattern consisting of higher intakes of vegetables, fruits, legumes, whole grains, nuts and seeds, with some vegetable oils, lowfat dairy, lean meat and poultry, and fatty fish, and lower intakes of red and processed meats, highfat dairy products, sugar-sweetened foods and drinks, and refined grains. Based on the totality of scientific evidence, DGAC concluded that reducing saturated fat intake and replacing it with unsaturated fats, specifically polyunsaturated fat, reduces the incidence of cardiovascular disease. DGAC also examines the relationship between seafood intake during adolescence and a range of developmental outcomes, but no conclusions were able to be drawn based on the evidence.
Expanded Populations Considered for the First Time: Birth to 24 Months, Pregnancy and Lactation
For the first time, DGAC’s Scientific Report considers evidence beyond individuals aged two and older, and examined nutrition evidence for the period from birth to 24 months, as well as during pregnancy and lactation. The DGAC developed food patterns for children 12 to 24 months based on whether or not the child receives human milk, infant formula, or a lacto-ovo vegetarian diet. The DGAC was not able to develop food patterns for birth to 12 months, but did develop potential combinations of complementary food and beverages that can be provided to infants during this stage. During pregnancy and lactation, DGAC found that following the same healthy dietary patterns for adults generally can reduce the risk of gestational diabetes, hypertensive disorders of pregnancy, and preterm birth. Additionally, DGAC concurred with existing recommendations that women who are pregnant or breastfeeding should consume at least 8 and up to 12 ounces of a variety of seafood per week from choices that are lower in methylmercury and higher in omega-3 fatty acids.
Evidence Regarding Dietary Patterns and Health Outcomes
The DGAC made the following specific findings with respect to the role of diet on the risk of disease or health issues:
- Risk of Cardiovascular Disease
Strong evidence indicates dietary patterns associated with decreased risk of cardiovascular disease include higher consumption of vegetables, fruits, whole grains, low-fat dairy, and seafood, and lower consumption of red and processed meat, and lower intakes of refined grains, and sugar-sweetened foods and beverages relative to less healthy patterns.
- Body Weight
Moderate evidence indicates dietary patterns emphasizing vegetables, fruits, and whole grains; seafood and legumes; moderate in dairy products (particularly low and non-fat dairy) and alcohol; lower in meats (including red and processed meats), and low in sugar-sweetened foods and beverages, and refined grains are associated with favorable outcomes related to body weight (including lower BMI, waist circumference, or percent body fat) or risk of obesity. Components of the dietary patterns associated with these favorable outcomes include higher intakes of unsaturated fats and lower intakes of saturated fats, cholesterol, and sodium.
- Risk of Type 2 Diabetes
Moderate evidence indicates that healthy dietary patterns higher in vegetables, fruits, and whole grains and lower in red and processed meats, high-fat dairy products, refined grains, and sweets/sugar-sweetened beverages reduce the risk of developing type 2 diabetes.
- Bone Health
Moderate evidence indicates that a dietary pattern higher in fruits, vegetables, legumes, nuts, low-fat dairy, whole grains, and fish, and lower in meats (particularly processed meats), sugar-sweetened beverages, and sweets is associated with favorable bone health outcomes in adults, primarily decreased risk of hip fracture.
- Risk of Cancer
Breast: Moderate evidence indicates that dietary patterns rich in vegetables, fruits, and whole grains, and lower in animal-source foods and refined carbohydrates, are associated with reduced risk of postmenopausal breast cancer. The data regarding these dietary patterns and premenopausal breast cancer risk point in the same direction, but the evidence is limited as fewer studies include premenopausal breast cancer.
Colon and Rectal: Moderate evidence indicates that dietary patterns higher in vegetables, fruits, legumes, whole grains, lean meats and seafood, and low-fat dairy and low in red and processed meats, saturated fat and sugar-sweetened beverages and sweets relative to other dietary patterns are associated with lower risk of colon and rectal cancer. Moderate evidence also indicates that dietary patterns that are higher in red and processed meats, French fries, potatoes, and sources of sugar (e.g., sugar-sweetened beverages, sweets and dessert foods) are associated with a greater colon and rectal cancer risk.
Lung: Limited evidence suggests that dietary patterns containing more frequent servings of vegetables, fruits, seafood, grains and cereals, legumes and lean vs higher fat meats and lower fat or non-fat dairy products may be associated with lower risk of lung cancer, primarily among former smokers and current smokers.
Prostate: Limited evidence suggests no relationship between dietary patterns and risk of prostate cancer.
- Neurocognitive Health
Limited evidence suggests that dietary patterns containing vegetables, fruits, unsaturated vegetable oils and/or nuts, legumes, and fish or seafood consumed during adulthood are associated with lower risk of age-related cognitive impairment and/or dementia.
- Sarcopenia (Loss of Skeletal Muscle Mass and Function)
- Limited evidence suggests that dietary patterns containing vegetables, fruits, unsaturated vegetable oils and/or nuts, legumes, and fish or seafood consumed during adulthood are associated with lower risk of age-related cognitive impairment and/or dementia.
We will continue to monitor developments related to the 2020-2025 Dietary Guidelines for Americans. If you have any questions regarding the Scientific Advisory Report or related issues please contact us.
Authored by Steve Steinborn and Samantha Dietle
Scientific Report of the 2020 Dietary Guidelines Advisory Committee, https://www.dietaryguidelines.gov/2020-advisory-committee-report (July 2020).
USDA Press Release, USDA Posts the 2020 Dietary Guidelines Advisory Committee’s Final Report (July 15, 2020), https://www.usda.gov/media/press-releases/2020/07/15/usda-posts-2020-dietary-guidelines-advisory-committees-final-report.
Comments may be submitted here: https://www.dietaryguidelines.gov/work-under-way/getinvolved/submit-comment.