The recent release of draft dietary guidance developed by a panel of experts convened by HHS and the Department of Agriculture has some in the medical community looking askance at the recommendations, both for what they do -- and for what they do not -- contain.
Noticeably missing from the Scientific Report of the 2015 Dietary Guidelines Advisory Committee(health.gov) (DGAC) are many of the traditional cautions about dietary cholesterol consumption. And what is new is a focus on sustainability of food resources.
"Although it has raised some eyebrows, the 2015 Dietary Guidelines Advisory Committee has not said anything that the medical community didn't already know," said Jennifer Frost, M.D., medical director for the AAFP Health of the Public and Science Division. "The average American eats a diet that is high in calories, saturated fat, refined grains and added sugars. This has contributed to the current epidemic of obesity and preventable chronic disease in this country."
- The Scientific Report of the 2015 Dietary Guidelines Advisory Committee has dropped many of the traditional cautions about dietary cholesterol consumption and added a focus on sustainability of food resources.
- The report is intended to serve as a starting point for revising the 2010 version of Dietary Guidelines for Americans.
- According to one FP expert, heeding the report's call for more consumption of fruits, vegetables and whole grains is key to addressing the nation's obesity epidemic.
The proposed guidance is intended to serve as a starting point for revising the 2010 version of Dietary Guidelines for Americans. After a 45-day comment period, HHS and the Agriculture Department will evaluate the DGAC's recommendations, as well as any public and agency comments, and finalize and disseminate the 2015 Dietary Guidelines for Americans.
Impetus Behind the 2015 Update
According to an executive summary(health.gov) of the 571-page report, the 2015 DGAC's work was guided by "two fundamental realities":
- About half of American adults -- some 117 million people -- have one or more preventable chronic diseases, and about two-thirds of U.S. adults -- nearly 155 million individuals -- are obese or overweight. Poor diet, overconsumption of calories and lack of physical activity are direct causes of these health problems.
- Individuals' nutrition, physical activity and other lifestyle-related behaviors are strongly influenced by their personal, social, organizational and environmental contexts and related systems. Making changes in diet and activity behaviors and related contexts and systems can improve health outcomes.
Charged with developing "food-based recommendations that are of public health importance for Americans ages 2 years and older," the DGAC began its work by examining the 2010 guidelines and identifying topics for which new scientific evidence was likely to be available.
The committee settled on five areas of focus:
- current status and trends in food and nutrient intakes,
- dietary patterns and health outcomes,
- individual lifestyle behavior change,
- food and physical activity environments and settings, and
- food sustainability and safety.
Food and Nutrient Intakes
Using data from the dietary component of the ongoing National Health and Nutrition Examination Survey, committee members determined that a number of nutrients are underconsumed, according to recommended intake levels. These so-called shortfall nutrients were vitamins A, C, D and E; calcium; folate; magnesium and potassium. In addition, iron intake was inadequate among adolescent and premenopausal females.
Furthermore, said DGAC members, some of the shortfall nutrients identified -- vitamin D, calcium, fiber and potassium overall and iron in young and premenopausal women -- are of particular public health concern because deficiencies of these nutrients are directly associated with adverse health outcomes.
In addition, the committee named two nutrients as being overconsumed: sodium and saturated fat. Two foods in particular -- refined grains and added sugars -- were also called out as being overconsumed.
Although DGAC members saw reason for cautious optimism among 2- to 5-year-olds, who do consume recommended amounts of fruits and dairy products, Americans overall have low intakes of food groups rich in the shortfall nutrients, such as vegetables, fruits, whole grains and dairy.
Still, said Frost, "The Dietary Guidelines Advisory Committee has not recommended eliminating any one food group, but encourages a diet higher in fruits, vegetables and whole grains."
Dietary Patterns and Health Outcomes
Describing common characteristics of healthy diets, according to the executive summary, entailed closely examining research that focused on dietary patterns, "because the totality of diet -- the combinations and quantities in which foods and nutrients are consumed -- may have synergistic and cumulative effects in health and disease."
Perhaps not surprisingly, the evidence committee members reviewed pointed to a healthy dietary pattern as being one that is:
- higher in vegetables, fruits, whole grains, low- or nonfat dairy, seafood, legumes and nuts;
- moderate in alcohol;
- lower in red and processed meat; and
- low in sugar-sweetened foods and drinks and refined grains.
The committee further noted that following a dietary pattern associated with reduced risks of cardiovascular disease (CVD), overweight and obesity confers positive benefits beyond these specific health outcome categories. Such dietary patterns can be achieved in multiple ways, said committee members, and should be tailored to an individual's biological, medical and sociocultural needs and preferences.
Individual Behavior Change and Environmental Support
No policy recommendations such as those included in the Dietary Guidelines for Americans, however, can be implemented without obtaining buy-in from those for whom they are intended. And doing that requires motivating and facilitating behavioral changes at the individual level.
To that end, the report offers a number of behavior change strategies that have shown success in boosting the effectiveness of diet-related interventions and enhancing overall health outcomes. Some of these strategies readily translate into an office-based setting, such as recommending that families reduce screen time, eat at fast food restaurants less often, share more meals at home, and work to self-monitor diet and body weight. Encouraging people to make healthier food choices by paying careful attention to food labels can be another helpful strategy.
Food environments also play a key role in determining individuals' ability to adhere to dietary goals, said the report's authors. Specifically, "the social, economic and cultural context in which individuals live may facilitate or hinder their ability to choose and consume dietary patterns that are consistent with the Dietary Guidelines." Household food insecurity, in particular, affects millions of Americans' access to a healthy diet.
Unfortunately, the types of preventive nutrition services that take social determinants of health into account are largely absent in the U.S. health system when it comes to systematically addressing nutrition-related health problems such as overweight and obesity, CVD, and type 2 diabetes.
Finally, noting that "access to sufficient, nutritious and safe food is an essential element of food security," the committee concluded that promoting food sustainability is key to ensuring this access for current and future generations.
This conclusion is consistent with the DGAC's other recommendations, according to Frost.
"There is no doubt that a diet that is higher in plant-based foods is healthier, and it is also associated with less of an impact on the environment," said Frost. "The Advisory Committee is being criticized for including sustainability in their recommendations, but access to sufficient and nutritious food has an important impact on health.
"Forty-nine million people in this country, including close to 9 million children, live in food-insecure households."
The guidelines report will be available for comment through April 8. Comments may be submitted online(health.gov).
Clinical Practice Guideline on Cholesterol: Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults (developed by the American College of Cardiology and American Heart Association and endorsed with qualifications by the AAFP)