Posts

2020-2025 Dietary Guidelines for Americans

The U.S. Departments of Agriculture (USDA) and Health and Human Services (HHS) are seeking public comments on topics and supporting scientific questions to inform the development of the 2020-2025 Dietary Guidelines for Americans. This is a new step in the development process. View the Federal Register Notice here.

Topics and questions proposed by USDA and HHS are based on four criteria: relevance, importance, potential federal impact, and avoiding duplication. The topics for 2020-2025 Dietary Guidelines are within a life stages approach, focusing on priority scientific questions from birth through older adulthood. In addition, the topics reflect a continued focus on patterns of what we eat and drink as a whole, on average and over time.

Learn more on the development of the dietary guidelines hereSubmit your comments here.

Listed below are the five life stages with proposed topics and scientific questions. The guidelines will also describe current dietary patterns, including intakes of food groups and nutrients, for each stage of life.

Infants and toddlers from birth to 24 months (healthy, full-term infants)

Topic Question(s)
Recommended duration of exclusive human milk or infant formula feeding What is the relationship between the duration of exclusive human milk or infant formula consumption and 1) growth, size, and body composition; 2) food allergies and other atopic allergic diseases; and 3) long-term health outcomes?
Frequency and volume of human milk and/or infant formula feeding What is the relationship between the frequency and volume of human milk and/or infant formula consumption and 1) micronutrient status; and 2) growth, size, and body composition?
Dietary supplements (e.g., iron, vitamin D, vitamin B12) What is the relationship between specific micronutrient supplements for infants fed human milk and/or infant formula and 1) micronutrient status; and 2) growth, size, and body composition?
Complementary foods and beverages*: Timing of introduction, types, and amounts

*Beverages (cow’s milk, water, 100% fruit juice, sugar-sweetened beverages, milk alternatives)

What is the relationship between complementary feeding and 1) micronutrient status; 2) growth, size, and body composition; 3) developmental milestones; 4) food allergies and other atopic allergic disease; and 5) bone health?

What is the relationship between complementary feeding, including foods and beverages, and achieving nutrient and food group recommendations of infants and toddlers?

Note: Evidence related to dietary patterns (including beverage patterns) consumed during the complementary feeding period will be considered as part of these questions.

 

Children and adolescents, ages 2-18 years old (with data reviewed by age group)

Topic Question(s)
Dietary patterns to promote health and normal growth and meet nutrient needs What is the relationship between specific dietary patterns (Dietary Guidelines-related, Mediterranean-style, Dietary Approaches to Stop Hypertension (DASH), vegetarian/vegan, and low-carbohydrate diets) consumed during childhood and adolescence and 1) growth, size, and body composition; and 2) bone health?

Are changes to the USDA Food Patterns needed based on the relationships identified? If so, how well do USDA Food Pattern variations meet nutrient recommendations for children and adolescents?

Beverages (cow’s milk, water, 100% fruit juice, sugar-sweetened beverages, milk alternatives, caffeinated beverages) What is the relationship between beverage consumption during childhood and adolescence and achieving nutrient and food group recommendations?
Added sugars What is the relationship between added sugars consumption during childhood and adolescence and achieving nutrient and food group recommendations?

How much added sugars can be accommodated in a healthy diet during childhood and adolescence while still meeting food group and nutrient needs?

 

Adults, ages 19-64 years old (with data reviewed by age group)

Topic Question(s)
Dietary patterns to promote health, prevent disease, and meet nutrient needs What is the relationship between specific dietary patterns (Dietary Guidelines-related, Mediterranean-style, Dietary Approaches to Stop Hypertension (DASH), vegetarian/vegan, and low-carbohydrate diets) consumed during adulthood and 1) body weight or obesity; 2) risk of cardiovascular disease; 3) risk of type 2 diabetes; and 4) risk of certain types of cancer?

Are changes to the USDA Food Patterns needed based on the relationships identified? If so, how well do USDA Food Pattern variations meet nutrient recommendations for adults?

Beverages (cow’s milk, water, 100% fruit juice, sugar-sweetened beverages, milk alternatives, caffeinated beverages) What is the relationship between beverage consumption during adulthood and achieving nutrient and food group recommendations?
Added sugars What is the relationship between added sugars consumption during adulthood and achieving nutrient and food group recommendations?

How much added sugars can be accommodated in a healthy diet during adulthood while still meeting food group and nutrient needs?

Saturated fats What is the relationship between saturated fats consumption (types and amounts) during adulthood and risk of cardiovascular disease?

 

Pregnancy and lactation

Topic Question(s)
How additional calorie needs should be met during pregnancy and lactation What is the relationship between specific dietary patterns (Dietary Guidelines-related, Mediterranean-style, Dietary Approaches to Stop Hypertension (DASH), vegetarian/vegan, and low-carbohydrate diets) consumed among women who are pregnant and 1) risk of gestational diabetes; 2) risk of hypertensive disorders during pregnancy; 3) gestational age at birth; and 4) birth weight standardized for gestational age and sex?

What is the relationship between specific dietary patterns (Dietary Guidelines-related, Mediterranean-style, Dietary Approaches to Stop Hypertension (DASH), vegetarian/vegan, and low-carbohydrate diets) consumed among women who are lactating and human milk composition and quantity?

Are changes to the USDA Food Patterns needed based on the relationships identified? If so, how well do USDA Food Pattern variations meet nutrient recommendations for women who are pregnant or lactating?

Dietary supplements (e.g., iron, folate, vitamin D) What is the relationship between micronutrient supplements consumed during pregnancy and lactation and 1) micronutrient status; 2) birth outcomes; and 3) human milk composition and quantity?
Diet during pregnancy and lactation and risk of food allergy in the infant What is the relationship between maternal diet during pregnancy and lactation and risk of infant allergies and other atopic allergic disease?
Seafood What is the relationship between seafood consumption during pregnancy and lactation and neurocognitive development of the infant?
Beverages (cow’s milk, water, 100% fruit juice, sugar-sweetened beverages, milk alternatives, caffeinated beverages) What is the relationship between beverage consumption during pregnancy and lactation and 1) achieving nutrient and food group recommendations; 2) birth outcomes; and 3) human milk composition and quantity?
Alcoholic beverages What is the relationship between maternal alcohol consumption during lactation and human milk composition and quantity?

 

Older adults, ages 65 years and older (with data reviewed by age group)

Topic Question(s)
Dietary patterns to promote health, prevent disease, and meet nutrient needs What is the relationship between specific dietary patterns (Dietary Guidelines-related, Mediterranean-style, Dietary Approaches to Stop Hypertension (DASH), vegetarian/vegan, and low-carbohydrate diets) consumed across the lifespan and 1) body weight or obesity; 2) risk of cardiovascular disease; 3) risk of type 2 diabetes; 4) risk of certain types of cancer; and 5) risk of osteoporosis?

What modifications to dietary patterns are effective in preventing or reversing declines in muscle mass or bone density in older adults?

Are changes to the USDA Food Patterns needed based on the relationships identified? If so, how well do USDA Food Pattern variations meet nutrient recommendations for older adults, age 65-80 years and those age 81+ years?

Specific nutritional needs related to older adults What modifications to food and beverage choices promote meeting nutrient needs in older adults with impaired dentition, dry mouth, or other aspects of aging that interfere with food and beverage consumption?

Comments are accepted through March 30, 2018. If you have a new topic or question to suggest, provide a brief summary including information pertaining to the four prioritization criteria. After the review of comments and finalization of topics and supporting questions, USDA and HHS will post a public call for the Dietary Guidelines Advisory Committee nominations.

Read more about the Dietary Guidelines here.

If you have any suggestions to inform ASN’s comments please reach out to Sarah Ohlhorst, Senior Director of Advocacy and Science Policy, at sohlhorst@nutrition.org or 240-428-3647.

 

 

While debates about the relative healthfulness of carbohydrates/type of fat/salt/sweeteners/etc. never cease, there is one nutritional message that can unite (almost) anyone: eat less processed foods. On the surface, this seems obvious; after all, the top sources of calories for adults in the US include grain-based desserts, burgers, sugar-sweetened beverages and chips (1,2), which are certainly not what dietary recommendations are going for. But when we pose “What are the effects of food processing on health?” as a scientific question, things suddenly become very complex. Is there a consensus on what food processing is? Is all food processing unhealthy? What research has been done on processed food?

What is Processed Food?

First, we should start on the tricky subject of definitions.

Jones and Clemens published a nice summary of how various organizations differ in their definitions of “processed food” (3). The United States Department of Agriculture and other government organizations, for example, tend to use a broad definition that includes any changes from a natural state – such as washing, heating, and cooking, to adding preservatives, flavors, additives, etc. The American Institute for Cancer Research uses the term “minimally processed” to denote vegetables, grains, and beans prepared without much added to them, or minimal refining. Then there is the “NOVA” system, an attempt by Dr. Carlos Monteiro and colleagues to categorize food processing into: “unprocessed or minimally processed foods”, which are essentially unmodified from nature or include light processing such as drying, boiling, freezing, etc., “processed culinary ingredients”, “processed foods”, and “ultra-processed foods” as the extreme, which includes foods made with ingredients with limited “unprocessed foods”, such as concentrated energy sources like sugars, oils, fat, salt, extracts like casein, lactose, and whey, or additives like dyes, flavors, sweeteners, etc. (4). There doesn’t appear to be good published data on what the public considers processed food, although the International Food Information Council (IFIC) has developed definitions with input from consumer focus groups, discussed below.

What the Critics Say

Some critiques of definitions push against a broad classification of food processing because it could put washing an apple and baking a cookie in the same basket. To this end, while the NOVA system is an attempt to standardize food processing classification for study, not everyone agrees with it. For instance, Dr. Mike Gibney and colleagues published a commentary last month in AJCN arguing that the system is not superior to using associations of nutrient intakes with disease (5). In essence, they argue that the NOVA definition of “ultra-processed” foods and beverages is too subjective and simplistic; that classifying solely by processing would not be of use to study disease links to specific micronutrients (i.e., goiter, allergies and intolerances, anemia, etc.); that it does not improve upon using already established dietary pattern analysis in research; that analysis of the NOVA system indicates that it does not predict nutrients that are suggested to be increased by processed foods such as fat and salt; that certain nutritional requirements such as folic acid could not be met with solely unprocessed foods; and that there is little evidence to date that processing relates to measures of satiety or “hyper-palatability”/”food addiction”. Further, changes to modern eating that relate to consuming more energy including increased portion sizes and energy density, may not necessarily be related to food processing. (As such, processing can be used to formulate smaller portion sizes and reduce energy density.)

Similarly, the 2014 American Society for Nutrition scientific statement on the nutritional role of processed foods by Dr. Connie Weaver and colleagues (6) takes issue with using the NOVA classification based on subjectivity, favoring instead IFIC definitions of processed foods as described below:

Type of Food Examples
Foods that require little processing or production (also called “minimally processed”). Washed and packaged fruits and vegetables; bagged salads; roasted and ground nuts and coffee beans
Foods processed to help preserve and enhance nutrients and freshness of foods at their peak. Canned tuna, beans and tomatoes; frozen fruits and vegetables; pureed and jarred baby foods
Foods that combine ingredients such as sweeteners, spices, oils, flavors, colors, and preservatives to improve safety and taste and/or add visual appeal. (Does not include “ready-to-eat” foods listed below.) Some packaged foods, such as instant potato mix, rice, cake mix, jarred tomato sauce, spice mixes, dressings and sauces, and gelatin
“Ready-to-eat” foods needing minimal or no preparation. Breakfast cereal, flavored oatmeal, crackers, jams and jellies, nut butters, ice cream, yogurt, garlic bread, granola bars, cookies, fruit chews, rotisserie chicken, luncheon meats, honey-baked ham, cheese spreads, fruit drinks and carbonated beverages
Foods packaged to stay fresh and save time Prepared deli foods and frozen meals, entrées, pot pies and pizzas

Republished from http://www.foodinsight.org/sites/default/files/IFIC_Handout1_high_res.pdf

The statement addressed how processed foods contribute to the health and nutrition of populations, stakeholders in improving diet, and research still needed. Analysis of foods that provide nutrient enrichment and fortification (added by processing) indicates that much of the population would fall below adequate intakes for several nutrients. On the other hand, on average they contribute to nutrients that are recommended to be limited such as added sugar, sodium, saturated fat, and calories. They critique the term “ultra-processed” because the degree of processing does not necessarily reflect nutrient content of a food. The paper also summarizes what the future of processed food should look like to better address nutritional and food security around the world, including more cross-discipline collaboration to improve upon processed products and better communication between consumers and relevant stakeholders (6). It also remains to be seen whether the NOVA classification system would lead consumers to choose better diets compared to healthy diet patterns developed by nutrient epidemiology such as MyPlate, DASH, or Mediterranean-style diets, which can include foods with various levels of processing (7).

Thus, depending on how you define it, food processing can contribute necessary nutrients but also nutrients that should be reduced, and how different forms of processing may affect health is understudied.

Research on Processed Foods

Most research on “processed foods” as a whole-diet approach has come from epidemiological studies or animal experiments. Many challenges exist that may prohibit effective research from being done, including defining and classifying processed foods, accurate recalling of foods in dietary surveys, utilizing suitable comparisons, getting study subjects to stay on an assigned diet for the necessary period of time, etc.

Instead of looking at processing, per se, as predictive of health effects, much research currently looks at individual aspects of food processing that may contribute to increased (or decreased) health risks. For example, my dissertation research focuses on dietary phosphorus, which is widely utilized as a food additive (8). Growing evidence suggests that excess phosphorus in the diet, particularly in the form that is added for processing purposes, may increase risks for cardiovascular and bone disease, particularly in those who have kidney disease. For example, a human trial directly compared foods with elevated levels of phosphorus additives vs. those that do not have additives and measured surrogate outcomes for bone and mineral metabolism, and observed changes that would predict long-term bone loss (9). For more, see recent reviews from our group (10,11). It is, however, difficult to definitively tease out the effect of individual components like phosphorus additives to long-term health from the whole food packages that they accompany.

An upcoming trial by Dr. Kevin Hall and others will test the effect of “ultra-processed foods” (based on the NOVA definition) in a highly controlled setting to see what effect on insulin sensitivity and other outcomes such foods have that should prove very interesting and continue the discussion on the utility of such classification schemes (12).

Conclusion

Like any nutrition guidance, we must rely on imperfect evidence to communicate dietary recommendations. Which is why telling the public to choose alternatives to “processed foods” when possible is likely an appropriate message despite scientific disagreement on classifications and health implications. Indeed, the 2015-2020 Dietary Guidelines for Americans contain 25 instances and the scientific report 67 instances of the word “processed” (13,14), in context implying that we should limit processed food, mostly focusing on processed meats where more research has been done. This is because processed foods tend to contribute nutrients that Americans already consume high amounts of, such as sodium and saturated fat. At the same time, it will be interesting to see the results of natural experiments such as Brazil’s Dietary Guidelines, which put the focus on food processing instead of nutrient levels (15). It is an area ripe for research and cross-disciplinary collaborations.

 

 

References

  1. https://www.cnpp.usda.gov/sites/default/files/dietary_guidelines_for_americans/PolicyDoc.pdf
  2. https://health.gov/dietaryguidelines/2015-scientific-report/pdfs/scientific-report-of-the-2015-dietary-guidelines-advisory-committee.pdf
  3. http://aaccipublications.aaccnet.org/doi/pdf/10.1094/CFW-62-3-0120
  4. https://www.researchgate.net/profile/Geoffrey_Cannon/publication/315497241_The_UN_Decade_of_Nutrition_the_NOVA_food_classification_and_the_trouble_with_ultra-processing/links/58d2c71aa6fdccd24d43bcbf/The-UN-Decade-of-Nutrition-the-NOVA-food-classification-and-the-trouble-with-ultra-processing.pdf
  5. http://ajcn.nutrition.org/content/106/3/717.full.pdf
  6. http://ajcn.nutrition.org/content/99/6/1525.full.pdf
  7. http://aaccipublications.aaccnet.org/doi/pdf/10.1094/CFW-62-4-0182
  8. http://advances.nutrition.org/content/5/1/104.full
  9. https://academic.oup.com/jcem/article-lookup/doi/10.1210/jc.2015-2279
  10. https://link.springer.com/article/10.1007%2Fs11914-017-0398-4
  11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5503680
  12. https://clinicaltrials.gov/ct2/show/NCT03189121
  13. https://health.gov/dietaryguidelines/2015/resources/2015-2020_Dietary_Guidelines.pdf
  14. https://health.gov/dietaryguidelines/2015-scientific-report/PDFs/Scientific-Report-of-the-2015-Dietary-Guidelines-Advisory-Committee.pdf
  15. http://www.fao.org/nutrition/education/food-dietary-guidelines/regions/brazil/en/

 

Corporate wellness

Registered dietitian nutritionists (RDNs) are best known for their roles in clinical nutrition, food service management, community nutrition, and public policy. However, there is increasing opportunity for RDNs to expand their job search into the private sector. Employers across the United States are implementing corporate wellness programs to increase employee health and reduce their healthcare costs. A 2010 study found that for every $1 an employer spends on corporate wellness, they save $4 on health care costs and absenteeism (1). This is an obvious incentive for any business, small or large, to implement a corporate wellness program. So much so that the 2016 Employer Health Benefits Survey showed that 46% of small businesses and 83% of large companies provide some sort of corporate wellness program to their employees (2). With growing popularity, these programs are excellent opportunities for RDNs to explore new employment options and reach new clientele.

When searching through corporate wellness providers, I quickly learned that the term “corporate wellness” could take on many different definitions. Platforms varied from one-on-one services, to software packages, to interactive phone apps. Services mostly included diet and exercise initiatives but some also provided physical therapy, massage therapy, mindfulness, and meditation. Overall, these programs are designed to prevent the development of chronic diseases by identifying risk factors and implementing lifestyle changes to reduce those risks.

In addition to lowering employer costs and improving employee health, corporate wellness may also address the 2015-2020 Dietary Guidelines for Americans, which emphasize the need to “support healthy eating patterns for all” (3). Corporations are like communities that allow individuals to interact every day, share comparable work experience, possess similar values, and likely have similar education backgrounds. As such, the corporate environment is a great opportunity to stimulate support and discussion around nutrition and health issues. By creating a culture of health at work, we are more likely to create a culture of health at home, with friends, and eventually in the community.

With the many potential benefits of corporate wellness programs, how are RDNs utilized in these programs? I had the pleasure of interviewing the founder and owner of Family Food LLC, a corporate wellness provider based out of Philadelphia. Krista Yoder Latortue is an advocate for the use of RDNs to design and implement corporate wellness initiatives.

“When people are spending the bulk of their day in a work environment, meeting them at work increases the public’s accessibility to Registered Dietitian Nutritionists (RDNs). Additionally, with the increased demand for corporate wellness, it is essential that RDNs, the nutrition experts, lead corporate wellness initiatives to ensure evidence-based nutrition interventions are being used”

Unfortunately, I don’t think every corporate wellness provider thinks like Latortue. After looking at websites of many corporate wellness programs, I began to question the quality of services being provided. Of the 25 companies I looked at, only 9 of them clearly stated they had RDNs on staff, on the executive team, or working as health coaches. Others provided services from nurses, personal trainers, physiologists, or even“company certified wellness coaches,” with no description of the certification process. Latortue expressed her concern about programs that don’t utilize the skills of RDNs.

“If nutrition education is being provided by unqualified providers, the chances of actually reducing employee health care costs decreases. Not only do they waste money on paying for a program, they continue to lose money to poor employee health. It is important to educate companies and wellness committees about the importance of using qualified health professionals, like RDNs, to provide corporate wellness programs.”

In a study that examined 150 corporate and hospital wellness programs, registered dietitians were more likely to work for hospital-based wellness programs and not corporate wellness programs (4). RDNs have classically been employed in clinical settings, and branching into the corporate world may be challenging. I asked Latortue how RDNs interested in corporate wellness should get involved.

Pay attention to local groups in your area that may be forming around corporate wellness and get involved to be the voice of RDNs, the nutrition experts”

As corporate wellness continues to grow, it is imperative that RDNs are on the forefront of the services being provided. Working in corporate wellness is an opportunity for RDNs that are interested in preventive care and lifestyle modification, enjoy working with individuals, and are passionate about shaping the nutrition and health beliefs of society. RDNs in corporate wellness also have a chance to increase public knowledge of what RDNs do, who we are, and why we are the trusted experts in nutrition.

 

  1. Baicker, K., Cutler, D. & Song, Z. Workplace wellness programs can generate savings. Health Aff. Proj. Hope 29, 304-311 (2010).
  2. 2016 Employer Health Benefits Survey-Summary of Findings. The Henry J. Kaiser Family Foundation (2016).
  3. S. Department of Health and Human Services and U.S. Department of Agriculture.2015 – 2020 Dietary Guidelines for Americans. 8th Edition. December 2015. Available at http://health.gov/dietaryguidelines/2015/guidelines/.
  4. Hickerson, M. & Gregoire, M. Characteristics of the Nutrition Provider in Corporate and Hospital Wellness Programs. Am. Diet. Assoc. 92, 339-341 (1992).

 

 

USDA Logo
By: R. Alex Coots, Student Blogger

The below interview is a continuation of an interview with Angela Tagtow, Executive Director of the Center for Nutrition Policy and Promotion at the USDA. Part 1 of this interview can be found here.

Tell me about the challenges of nutrition policy.

I imagine health policy falling into one of two categories, little-p policy (LPP) or big-p policy (BPP). LPP is a socioecological approach to policy, using individuals and organizations to make decisions to improve public health that don’t require an elected official. BPP requires elected officials to create broader, more top-down initiatives to improve public health. Both types of policy working in concert can create greater collective impact.

Many people see BPP as the primary driver of policy, but LPP can be very effective to improve community health. The Northeast Iowa Food and Fitness Initiative exemplifies the power of LPP. Through the initiative they recruited hundreds of community stakeholders to make commitments to improve public health whether that is at home, school, workplace or throughout the community. Starting the initiative was a slow process built on networking and strengthening relationships, but proved to make an impact in the lives of community members.

BPP also creates change, but has its own challenges. It can take several years for State or Federal programs to be fully implemented. For example, the Healthy Hunger-Free Kids Act was signed into law back in 2010, and we’re still seeing elements roll out. At the Federal level, Congress is another aspect that makes BPP challenging. Each Congressperson has a different perspective and set of values with respect to healthy food access, nutrition, public health. The ability to recognize their priorities and influencers is an important part of building support behind an initiative.

Given the number of different opinions and interests regarding public health, do you think there’s a way to make everyone happy?

There’s always going to be struggle. Every organization out there has a set of goals that are different from the next organization. Industry has an interest to protect its products and public health has an interest to keep people healthy. These goals are not always aligned, so there are challenges.

The media often reports on about industry trying to make changes to their offerings in the name of public health. Do you think these efforts are genuine?

Not all industry should be discounted. Some companies do consider how their products and services contribute to public health and are trying to make a difference. But for others, they need to evaluate whether they are doing all that they could be doing.

 

What are some of the future goals for the USDA and the CNPP?

The CNPP does much more than just produce the Dietary Guidelines for Americans (DGA) and the iconic MyPlate. The Nutrition Evidence Library, a very rigorous review of the literature that directly informs the DGA. The CNPP also makes many tools and online resources available to assist individuals with eating and physical activity goals. ChooseMyPlate.gov and Supertracker.usda.gov are dynamic online resources for individual, families and professionals that put the Dietary Guidelines for Americans into action.

In the near term, the launch of the 2015 Dietary Guidelines for Americans and the Healthy Hunger-Free Kids Act are the top priorities. Some policymakers are challenging the validity of improving child health, and the House and Senate have inserted language in appropriation bills that will restrict USDA and HHS’s  abilities to create the Dietary Guidelines. It’s a very interesting political time regarding advancing the nutritional health of Americans.

Do you have any final advice for students?

Yes, be engaged. Having a good grasp of the content knowledge and political processes are good, but having contacts and networks is just as important. Knowing key people who create change and understanding how to work with them will allow you to be more effective in your endeavors. We need more people to get engaged with nutrition and public health efforts.

By Banaz Al-khalidi

First released in 1980, the Dietary Guidelines for Americans are updated and jointly published by the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (HHS) every 5 years. These guidelines provide recommendations on nutrition and physical activity for Americans aged 2 and older, and are the driving force behind Federal nutrition policies, nutrition education and food procurement programs. As such, these guidelines are used by both the public and industry, and by a wide variety of audiences including educators, health professionals and government agencies.

Earlier the 2015 Dietary Guidelines Advisory Committee (DGAC) released a Scientific Report based on the latest evidence, which will shape the finalized guidelines later this year. The committee’s work was influenced by two fundamental connections between nutrition and lifestyle-related health issues facing the U.S population:

1) Chronic diseases, overweight and obesity: about half of all American adults (~117 million) have one or more preventable chronic diseases such as type 2 diabetes, cardiovascular diseases, hypertension, and diet related cancers, and about two-thirds of adults and one-third of children are overweight or obese due to poor dietary habits and physical inactivity.
2) Food environment and settings: diet and lifestyle behaviors are strongly influenced by personal, social, organizational, and environmental context and systems. As such, the DGAC developed their recommendations based on a conceptual model of socio-ecological framework to provide recommendations at the individual, social, organizational, and environmental level.

What does the DGAC’s report say about the latest research on diet and lifestyle-related health outcomes?

The DGAC found that the current average American diet is low in vegetables, fruits, and whole grains and too high in refined grains, added sugars, saturated fat, and sodium. Furthermore, inadequate consumption of vitamin D, calcium, fiber, and potassium were categorized as nutrients of public health concern for the majority of the U.S population. Lifestyle-related health problems in the U.S. have persisted for more than 2 decades and the DGAC’s report calls for urgent preventative actions at the national, state, and local community levels. The DGAC recommended a shift in focus to a more environmentally friendly, sustainable plant-based diet that focuses on whole foods rather than specific nutrients. The overall body of evidence examined by the committee is summarized below:

“A diet higher in plant-based foods, such as vegetables, fruits, whole grains, legumes, nuts, and seeds, and lower in calories and animal based foods is more health promoting and is associated with less environmental impact than is the current U.S. diet.”

This is not to say that any food groups need to be eliminated completely to improve health and sustainability outcomes. In fact, the DGAC recommended three dietary patterns to provide options that can be adopted by the U.S. population and are also aligned with lower environmental impacts. These dietary patterns include the Healthy U.S. style Pattern, the Healthy Mediterranean style Pattern, and the Healthy Vegetarian Pattern. Furthermore, the 2015 DGAC left out cholesterol restrictions where previously, the 2010 DGAs recommended that cholesterol intake be limited to no more than 300 mg/day. The up-to-date evidence on cholesterol showed no substantial relationship between dietary consumption of cholesterol and blood cholesterol. Thus, the 2015 DGAC concluded, “Cholesterol is not a nutrient of concern for overconsumption.”

The message is clear—the 2015 DGAC recommends the U.S population consume dietary patterns that are rich in vegetables, fruits, whole grains, seafood, legumes, and nuts; moderate in low- and non-fat dairy products and alcohol; lower in red and processed meat; and low in saturated fat (less than 10% of total calories consumed per day), added sugars (maximum of 10% of total calories consumed per day), and sodium (2,300 mg per day or age-appropriate Dietary Reference Intake amount). Whether the USDA and the HHS will choose to adopt or ignore these recommendations put forth by the 2015 DGAC remains uncertain at this point. Meanwhile, dozens of health and environmental groups support the committee’s recommendations regarding sustainability, as viewed in the open letter found at My Plate My Planet, Food for a Sustainable Nation.

The advisory recommendations put forth by the 2015 DGAC are also closely aligned with recent research highlighting the urgency of shifting global diets, where healthy dietary patterns (i.e. Vegetarian, Pescetarian, and Mediterranean diets) are found to be associated with more favorable health as well as environmental outcomes. Thus, the available data strongly suggest that diets that are higher in plant-based foods will not only improve personal and public health, but also boost our planet’s health via “weight” reduction in greenhouse gases mainly due to reduction in livestock production.

By Ann Liu, PhD

Systematic reviews are the basis for nutrition policy and guidance, but gaps in the evidence base can impact recommendations. Presenters at the symposium “Creating the Future of Evidence-Based Nutrition Recommendations, Using Lipid Research Case Studies” sponsored by ILSI North America spoke on various aspects that inform the process of developing dietary guidance and its implementation on Saturday, March 28. Major policy and regulatory groups such as the Dietary Guidelines for Americans Scientific Advisory Committee, American Heart Association, and the Institute of Medicine use systematic reviews as the basis for their decision making, but often the ability to make recommendations can be hampered by a lack of strong evidence.

The process of developing evidence-based reviews, such as the one used by the USDA Nutrition Evidence Library, must be rigorous, transparent, and minimize bias, because these reviews inform federal nutrition policy and programs. At the outset, key systematic review questions are developed which should reflect important decisional dilemmas in public health nutrition guidance.

The next critical step is deciding on inclusion and exclusion criteria, which determines what literature is included in the evidence base. Criteria that may be considered include study design, study duration, size of groups, drop out rates, and the health status of participants. This process is thoroughly documented and transparent so it can easily be determined why a study was included or excluded. The evidence base will go on to be evaluated by expert panels in order to make recommendations and guidances.

How can scientists ensure that their research is included in the evidence base?

– When designing studies, it is important to consider the validity of the study design, the impact of endpoints, and the relevance and feasibility of interventions. Are the outcomes meaningful and are they translatable? If not, what additional information do you need? Researchers can also use the gaps in the literature identified in Nutrition Evidence Library systematic reviews to inform future investigations.
– If studying chronic disease risk, use validated surrogate biomarkers.
– Carefully consider your comparator group. One of the most common reasons studies are discounted from systematic reviews is they did not include appropriate control groups.
– Once you are ready to report your results, follow established reporting standards such as the Consolidated Standards of Reporting Trials (CONSORT) for randomized clinical trials or the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. This can help ensure that key information is included and is available for data abstraction in future systematic reviews and meta-analyses.
– Participate in the process. Once draft reports such as the Dietary Guidelines for Americans Scientific Report are issued, there is the opportunity for public comment. Feedback from scientists with expertise is strongly encouraged.