Part D. Chapter 5: Food Sustainability and Safety
In this chapter, the DGAC addresses food and nutrition issues that will inform public health action and policies to promote the health of the population through sustainable diets and food safety. An important reason for addressing sustainable diets, a new area for the DGAC, is to have alignment and consistency in dietary guidance that promotes both health and sustainability. This also recognizes the significant impact of food and beverages on environmental outcomes, from farm to plate to waste disposal, and, therefore, the need for dietary guidance to include the wider issue of sustainability. Addressing this complex challenge is essential to ensure a healthy food supply will be available for future generations. The availability and acceptability of healthy and sustainable food choices will be necessary to attain food security for the U.S. population over time. Integral to this issue is how dietary guidance and individual food choices influence the nations capacity to meet the nutritional needs of the U.S. population. Food sustainability and food safety are also interrelated in generating a secure food supply. This chapter focuses on both sustainable diets and food safety.
Two definitions are relevant to the material presented in this chapter. These terms were slightly modified from the Food and Agriculture Organization (FAO) definitions to operationalize them for the Committees work.1, 2
Sustainable diets: Sustainable diets are 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.
Food security: Food security exists when all people now, and in the future, have access to sufficient, safe, and nutritious food to maintain a healthy and active life.
The topic of current food security was addressed in Chapter 3 and to some extent in Chapter 4, where federal food programs were discussed. The topic of long-term food security was addressed within this chapter through examination of the evidence on sustainable diets.
The environmental impact of food production is considerable and if natural resources such as land, water and energy are not conserved and managed optimally, they will be strained and potentially lost. The global production of food is responsible for 80 percent of deforestation, more than 70 percent of fresh water use, and up to 30 percent of human-generated greenhouse gas (GHG) emissions.3 It also is the largest cause of species biodiversity loss.3 The capacity to produce adequate food in the future is constrained by land use, declining soil fertility, unsustainable water use, and over-fishing of the marine environment.4 Climate change, shifts in population dietary patterns and demand for food products, energy costs, and population growth will continue to put additional pressures on available natural resources. Meeting current and future food needs will depend on two concurrent approaches: altering individual and population dietary choices and patterns and developing agricultural and production practices that reduce environmental impacts and conserve resources, while still meeting food and nutrition needs. In this chapter, the Committee focuses primarily on the former, examining the effect of population- level dietary choices on sustainability.
Foods vary widely in the type and amount of resources required for production, so as population-level consumer demand impacts food production (and imports) it will also indirectly influence how and to what extent resources are used.3 As the focus of the dietary guidelines is to shift consumer eating habits toward healthier alternatives, it is imperative that, in this context, the shift also involve movement toward less resource-intensive diets. Individual and population-level adoption of more sustainable diets can change consumer demand away from more resource-intensive foods to foods that have a lower environmental impact.3
In this chapter, the DGAC has used an evidence-based approach to evaluate the foods and food components that improve the sustainability of dietary patterns as a step toward this desirable goal. The approach used was to determine dietary patterns that are nutritionally adequate and promote health, while at the same time are more protective of natural resources. This type of comprehensive strategy also has been used by intergovernmental organizations. For example, the FAO has identified the Mediterranean diet as an example of a sustainable diet due to its emphasis on biodiversity and smaller meat portions,5 and the European Commission has developed a “2020 Live Well Diet” to reduce GHG emissions through diet change.6
It should be noted that research in the area of dietary patterns and sustainability is rapidly evolving and the methodologies for determining dietary patterns in populations and Life Cycle Analysis of foods/food components and environmental outcomes have made significant advances in recent years.7, 8 This is exemplified by the size of evidence base for this question and the fact that several relevant articles have been published even since the close of the 2015 DGAC Nutrition Evidence Library (NEL) scientific review period for this topic.9-11
Figure D5.1 outlines the interconnected elements that the DGAC believes are necessary based on current evidence to develop sustainable diets. Sustainable diets are realized by developing a food system that embraces a core set of values illustrated in the figure. These values need to be implemented through robust private and public sector partnerships, practices and policies across the supply chain, extending from farms to distribution and consumption. New well-coordinated policies that include, but are not limited to, agriculture, economics, transportation, energy, water use, and dietary guidance need to be developed. Behaviors of all participants in the food system are central to creating and supporting sustainable diets.
Figure D5.1: Elements needed for sustainable diets
Although the addition of sustainability topics in the Scientific Report of the 2015 Dietary Guidelines Advisory Committee is new in 2015 it was acknowledged as a topic of strong relevance but not addressed by the 2010 DGAC. It has been a widely discussed aspect of nutrition policy for the past decade in countries such as Germany, Sweden and other Nordic countries, the Netherlands, Australia, and Brazil. For example, in the Netherlands, the Advisory report, Guidelines for a Healthy Diet: The Ecological Perspective focused on guidelines that inform both health and ecological benefits using an evidence-based strategy.12 Nordic countries, such as Sweden, have been researching sustainability and dietary choice since the late 1990s with the most recent edition of the Nordic Nutrition Recommendations (NNR) including an emphasis on the environmental impact of dietary recommendations.13 The German Dietary Guidelines developed a “sustainable shopping basket,” which is a consumer guide for shopping in a more sustainable way.14 Overall, the environmentally sustainable dietary guidance from these countries includes elements identified in this DGAC report as consistent with the extant data: a focus on decreasing meat consumption, choosing seafood from non-threatened stocks, eating more plants and plant-based products, reducing energy intake, and reducing waste. Non-governmental and international organizations, such as the United Nations, the FAO, the Sustainable Development Commission in the United Kingdom (UK), the Institute of Medicine (IOM), the Academy of Nutrition and Dietetics, and the National Research Council have all convened working groups and commissioned reports on sustainable diets.2, 15-19 Overall, it is clear that environmental sustainability adds further dimensions to dietary guidance; not just what we eat but where and how food production, processing, and transportation are managed, and waste is decreased.
The DGAC focused on two main topic areas related to sustainability: dietary patterns and seafood. The identification of dietary patterns that are sustainable is a first step toward driving consumer behavior change and demand and supply-chain changes. Furthermore, dietary patterns were an overall focus area of the 2015 DGAC and allow for a more comprehensive approach to total diet and health. This approach is particularly well suited for assessing overall environmental impacts of food consumption, as all food components of a dietary pattern are identified, and keeping within the context of health outcomes that have been documented for different dietary patterns. The topic area of seafood was chosen because consumption has well-established health benefits and the 2010 DGAC report highlighted the concern for seafood sustainability and called for a better understanding of the environmental impact of aquaculture on seafood contaminants. Meeting these recommendations, however, increases demand for seafood production and this, in turn, poses challenges, as certain seafood species are depleted and marine waters are over fished, while most other species are at the limits of sustainable harvesting. To meet these challenges, as world capture fisheries production has leveled off, aquaculture production has increased to meet demand.20 Therefore, building upon the 2010 DGAC report, the 2015 DGAC addressed the health benefits (nutrients) versus the risks (contaminants) of farm-raised (aquaculture) compared to wild-caught seafood and reviewed the evidence on the worldwide capacity to produce enough seafood to meet dietary guidelines. Overall, promoting sustainable fishing and aquaculture can provide an example for broader ecosystem stewardship.20
Food safety was first introduced in the 2000 Dietary Guidelines for Americans, and the recognition of the importance of food safety continued through the 2010 report. This chapter updates the 2010 DGAC report related to food safety behaviors in the home environment and evaluates new topics of food safety concern with very current and/or updated evidence. The current/updated topics include the safety of beverages, specifically coffee and caffeine, and food additives, specifically aspartame, in the U.S. food supply.
In 2015, the DGAC addressed new topics of concern. For the first time, the DGAC addressed the safety of coffee/caffeine consumption, as well as the safety of consuming higher doses of caffeine in products such as some energy drinks. The food additive, aspartame, has been the only non-nutritive sweetener to be completely re-evaluated in recent years and the results of this reevaluation were deemed important because it includes the most recent science on aspartame and health. These topic areas were chosen for consideration because they are of high public health concern and very recent evidence has been published that significantly updates the knowledge base on health aspects related to caffeine and aspartame in the diet.
For 2015, the DGAC brought forward the updated food safety principles to reduce risk of foodborne illnesses. These principlesClean, Separate, Cook and Chillare cornerstones of the Fight BAC! (www.fightbac.org) educational messages developed by the Partnership for Food Safety Education, a collaboration with the Federal government. These messages are reinforced by other USDA educational materials, including the Be Food Safe (www.befoodsafe.gov) efforts; Is it Done Yet? (www.isitdoneyet.gov); and Thermy (www.fsis.usda.gov/thermy), which outline key elements in thermometer use and placement to ensure proper cooking of meat, poultry, seafood, and egg products. Additional consumer-friendly information on food safety is available at www.foodsafety.gov. The DGAC brought forward the guidance for consumers that has been updated since 2010 on recommended procedures for hand sanitation, washing fresh produce, preventing cross-contamination, and safe meat, poultry, seafood and egg cooking temperatures and thermometer use from the FDA, the Center for Disease Control (CDC) and the Food Safety and Inspection Service (FSIS). The updated food safety tables are located at the end of this chapter.