The Dietary Guidelines Advisory Committee recently released their Scientific Report for the 2015 Dietary Guidelines for Americans, scheduled to be published later this year. The surprise feature, somewhat quietly introduced late in the report, is a recommendation to consider sustainability when making food choices. @DrTomSherman
Georgetown University has produced a series of four videos with me, as they put it, “helping to digest the new dietary recommendations.”
In preparation for the 2015 edition of the Dietary Guidelines for Americans, the Secretaries of the U.S. Department of Health and Human Services (HHS) and U.S. Department of Agriculture (USDA) form a panel of experts in the fields of nutrition, medicine and public health to comprise the Dietary Guidelines Advisory Committee (DGAC). Beginning in 2013, the DGAC was tasked with reviewing the recent literature in order to collect the scientific data that many of us hope will be evidence-based dietary guidelines.
This week, the Secretaries released the DGAC recommendations report online, making it available for public review and comment. The U.S. Departments of Health and Human Services (HHS) and Agriculture (USDA) will consider this report, along with input from other federal agencies and comments from the public as they develop the 2015 Dietary Guidelines for Americans.
In general, I am very pleased with the Scientific Report, and feel the committee did a wonderful job fairly evaluating the scientific literature and making recommendations that can be defended on the basis of evidence. I am particularly pleased, and surprised, that the committee report contains recommendations that go beyond dietary considerations, for the first time recognizing that food choices cannot be considered independently of the intricate ecosystem of which they are part. More on that in a moment …
Highlights of the 2015 DGAC Scientific Report
The DGAC report makes very clear that the individual is at the innermost core of what the committee refers to as the “social-ecological model.” Essentially this recognizes that people do not make dietary and food choices in isolation of the their social and environmental contexts. The complicated figure below, which featured prominently in the introduction, expands on this concept. As shown, the individual is in the middle of the social-ecological model, and much of the report ultimately tries to motivate and facilitate behavioral change at the individual level.
The DGAC recognized that a dynamic interplay exists among individuals’ nutrition, physical activity, and other health-related lifestyle behaviors and their environmental and social contexts. Acknowledging this, the DGAC created a conceptual model based in part on the socio-ecological model to serve as an organizing framework for its report. The figure above shows how these personal, social, organizational, and environmental contexts and systems interact powerfully to influence individuals’ diet and physical activity behaviors and patterns and how diverse health outcomes result from this dynamic interplay.
In addition to the social-ecological model, the 2015 DGAC recommendations adopt a revised overall focus from the 2010 Guidelines for Americans. This focus was well articulated by my colleague and esteemed member of the DGAC, Dr. Lucile L. Adams-Campbell, Professor of Oncology and Associate Director, Minority Health & Health Disparities Research, in the Lombardi Comprehensive Cancer Center:
“The DGAC 2010 guidelines focused on nutrient-dense foods and beverages that contributed to achieving and maintaining a healthy weight, which differs significantly from the focus of the 2015 recommendations. The DGAC 2015 recommendations focus on major diet-related chronic diseases and other less common but important health outcomes associated with poor dietary quality with evidence that links improvements to modifiable lifestyle behaviors, particularly improved dietary patterns and physical activity. The 2015 recommendations reflect the shift in healthcare and public health settings towards prevention versus tertiary care incorporating the use of personalized diet, physical activity and lifestyle changes to promote individual and population health. The high rates of preventable chronic diseases continue to persist and disproportionately affect low-income and underserved communities. Also demonstrated is the need for environmental changes that involve multi-dimensional approaches and public-private partnerships to improve the quality of available food choices at the community and population levels inclusive of school, day care, worksites, healthcare and public health settings.”
I would list the following five elements of the DGAC recommendations as being the most significant, or significantly different from the 2010 Dietary Guidelines for Americans:
Sets a limit for “added sugar” to no more than 10% of all calories; currently, the average intake of added sugars for Americans is 13%. Interestingly, there are two somewhat surprising additions in the committee’s recommendations: Firstly, the report states: “Higher sugar-sweetened beverage taxes may encourage consumers to reduce sugar-sweetened beverage consumption …” and promotes “using the revenues from the higher sugar-sweetened beverage taxes for nutrition health promotion efforts or to subsidize fruits and vegetables could have public health benefits.” Secondly, the report recommends adding a line for added sugars on Nutrition Facts panels, expressed in teaspoons as well as grams, and with a new Daily Value. If adopted in the final Dietary Guidelines for Americans, these recommendations will be the most significant and result, I believe, in the greatest benefits to public health.
The report states: “Cholesterol is not a nutrient of concern for overconsumption.” The Scientific Report no longer recommends limits to the consumption of cholesterol, essentially rec0gnizing that research has consistently found no significant link between dietary cholesterol consumption and circulating levels of cholesterol.
Although this particular change is welcome news to those who enjoy eating eggs and seafood rich in cholesterol, it is going to be confusing to many people, not simply because it represents yet another nutritional reversal, but because it has been seized by a media which conflates the cholesterol recommendations with recent reports that the links between saturated fat and heart disease are not as clear as had been argued. Thus, a segment of the media is gleefully reporting “Butter is Back” articles and headlines.
I see this issue as a series of disconnects that should be summarized like this:
Disconnect #1: Dietary consumption of cholesterol does not significantly contribute to circulating levels of cholesterol, BUT elevated levels of LDL cholesterol, or low circulating levels of HDL cholesterol, remain a significant risk factor for heart disease.
Disconnect #2: Cholesterol is only found in foods derived from animals (meat, milk, eggs, etc), and many of these foods are rich in saturated fat, AND saturated fat does increase circulating levels of cholesterol, AND saturated fat remains a nutrient of concern in the DGAC report. Thus, those trying to manage their cholesterol will benefit by limiting their consumption of saturated fats. For many, therefore, the liberalization of cholesterol consumption recommendations should not be viewed as a license to eat abundant amounts of red meat. Even though the risks associated with saturated fat have been exaggerated for more than 50 years as part of a pattern of demonizing fats and cholesterol, which eventually led to the low fat recommendations that proved so disastrous to our nation’s health and weight (for more info, read this post), we cannot pretend that eating red meats is benign or healthful.
I found the comments of Dr. David Katz on cholesterol to be illuminating.
Recommends families reduce their consumption of red and processed meats. I was pleased to read that the committee goes on to report, “seafood should replace portions of terrestrial meat.” Although the data demonstrating the increased risks of cardiovascular disease, cancer, and overall mortality associated with red meat and processed meat consumption has been consistently replicated in the medical literature over the past several years, this literature is complicated and has been debated and hotly contested by many groups, and not simply the meat industry and Paleo diet adherents. I find the advice to limit red meat intake to be sensible, but these recommendations are viewed as an attack on the meat industry, even though this same industry has proven unable to mount an articulate, evidence-based response. The Physicians Committee for Responsible Medicine recently published a report detailing the shameless manner in which meat advocates skew the science. We may not understand why eating meat provides such an increased risk of mortality, but that does not change the observation.
The DGAC suggests a daily limit of 2,300 milligrams of sodium a day, in contrast to evidence—and the 2010 Dietary Guidelines—that 1,500 milligrams is a healthier goal for most adults.
Although I agree that 1,500 mg of sodium is a healthier goal, it is completely unrealistic unless major reforms are adopted, or legislated, by the processed food and restaurant industries. Thus, despite the Institute of Medicine’s 2010 recommendation to work towards the lower limit, even 2,300 mg per day will yield significant benefits. This reality is acknowledged in the report, which endorses the Institute of Medicine’s 2010 report and encourages gradual reductions of sodium in the food supply.
Coffee is one of the most commonly consumed, and dearly loved, beverages on the planet, third behind water and tea. Still, given our love and dependence on the drink, many fear to wake one morning to a headline that reads that coffee consumption causes elbow cancer or something similarly horrible. Quite the opposite has long been shown to be the case, and the DGAC recommendations not only acknowledge minimal health risks associated with drinking 3–5 cups of coffee per day, but essentially recommend drinking five cups per day, or the equivalent of ~400 mg caffeine, by citing the reduced risk of cardiovascular disease and type 2 diabetes who do so. Read the Washington Post story.
In my favorite highlight of the DGAC Scientific Report, the recommendations unambiguously state that Americans should consider the impact on sustainability and the environment when they are making food choices. This is an essential component of the social-ecological model, and may seem obvious and long overdue to many, but the explicit wording of the sustainability recommendation is a direct slap at a congress that recently attached a congressional directive to the recent spending bill that “expresses ‘concern’ that the Dietary Guidelines Advisory Committee ‘is showing an interest in incorporating agriculture production practices and environmental factors’ into their recommendations, and directs the Obama administration to ignore such factors in the next revision of the guidelines, which is due out next year” (see NPR story).
What is so wonderful about a dietary guideline that recognizes the reality of sustainability and the environment is that it perfectly encapsulates and reinforces many of the other recommendations in the report. The major findings regarding sustainable diets, for example, are that 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.” Perfectly said!
As part of the committee’s examination of nutrients in the American diet, it found that vegetables, fruits, whole grains, legumes, nuts, and seeds are insufficiently consumed, and that saturated fats, red and processed meats, sodium and added sugars are overly consumed. Evidence that the meat industry is the least sustainable means of food production, with the greatest environment costs, have been widely reported. Thus, seeking sustainability and minimizing environmental impact automatically steers one towards a plant-based diet, and by extension (arguably), organic farming strategies. Again, perfect!
In conclusion, I offer these two, not so simple, recommendations to building a path towards a better diet and improved health:
Give thought to sustainability and the environment when making food choices. Choosing, when possible, plant-based, organic foods obviates the concerns, and risks, associated with red and processed meats, pesticides, herbicides and fertilizers in your food.
Although I am an advocate for the Mediterranean-Style Diet (see this, and this, and this), for my family enjoys the flavors of a diet rich in fruits and vegetables, seafood, olive oil and wine, I agree with the writings of Dr. David L. Katz that most any diet, from a vegetarian diet to a Paleo diet, are more similar to each other than they are to a typical American diet, and should be encouraged. See Atlantic article.