When it comes to healthy eating, there’s a lot we already know.
Just take a look at the scientific report issued by the 2020 Dietary Guidelines Advisory Committee, the group of scientific experts behind the newly released 2020-2025 Dietary Guidelines for Americans. At 835 pages, the report spans a rigorous review of current research on dozens of topics, from whether eating peanuts early in life reduces the likelihood of peanut allergies (it probably does), to how much added sugar we can eat and still maintain a healthy diet (way less than what we’re eating now). It also outlines the broad contours of a healthy diet, which has changed little from past editions of the Dietary Guidelines: it’s typically higher in vegetables, fruits, legumes, whole grains, low- or non-fat dairy, lean meat and poultry, seafood, nuts, and unsalted vegetable oils, and lower in red and processed meats, sugar-sweetened foods and drinks, and refined grains.
But food is more than just nutrition. We also know that food can affect the health of many people before it even reaches our plates. For example, pollution caused by fertilizer runoff from farms have left communities without access to safe drinking water, while many of the people who produce our food don’t earn enough to afford healthy diets themselves. So, is it possible to eat in ways that promote health and produce better outcomes for our collective wellbeing, livelihoods, and natural resources? And what would it take to get us there?
These are complex questions, but critical ones—and if the federal government made it a national priority to answer them, we might have a chance at avoiding otherwise devastating consequences.
That’s why leading experts and scientific bodies, including the 2020 Dietary Guidelines Advisory Committee, are increasingly calling attention to the importance of research on sustainable diets. Though there is no official record of how much federal funding is currently supporting this field, funding for nutrition research across the board has remained stagnant for decades. Research funding at the intersection of food and agriculture issues, in particular, is decidedly inadequate to address the magnitude of the public health challenges before us, including climate change, threats to food security, and persistent poverty and health disparities.
Many, including UCS, are working to change that by advocating for greater government investment in sustainable diets research. Here are three of the most pressing questions that research can answer to enable more sustainable eating for all.
1. When it comes to healthy and environmentally sustainable diets, what exactly is on the menu?
Research on healthy and environmentally sustainable diets has seen extraordinary growth in recent years. According to UCS research, nearly 100 new scholarly articles were published on this topic between 2015 and 2019, including 22 articles focused specifically on US diets. For reference, that’s more than four times the number of articles published on the same topic between 2000 and 2015—in about a quarter of the time.
Much of this research agrees that, in general, healthy diets that are higher in plant-based foods and lower in animal-based foods are more environmentally sustainable—meaning they are often associated with reduced energy and land use, as well as less air and water pollution.
This is an important finding that enables us to take the first steps toward more sustainable diets—and each step is critical, given the urgency and magnitude of dual public health and climate crises. Indeed, a number of other countries already have acted on existing knowledge to incorporate sustainability into national dietary guidance.
But the more we know, the faster (and further) we can move forward.
For example, we need to better understand the impacts of all different kinds of dietary shifts that could improve health and sustainability, and the most effective ways to encourage such shifts at the individual, institutional, and societal levels. We also need to better understand how a wide variety of sustainable diets align with diverse cultures and culinary traditions. Both of these areas of research will be crucial to informing practical public health interventions and policy recommendations that can help all people make meaningful changes.
There are also challenges with available data and models. Many studies on sustainable diets rely on models called Life Cycle Assessments, which help estimate the cumulative environmental impacts of the foods we eat. For example, how much energy is required to process, package, and transport a pound of beef from the farm to the grocery store? How much land, water, and energy was required to raise the cattle? While a Life Cycle Assessment is useful in providing general estimates, it’s often based on averages that don’t account for key differences in production methods, for example, or regions. More data—and more diverse data sources—could make this an even more powerful and practical tool.
These and other outstanding research gaps prompted the Interagency Committee on Human Nutrition Research (ICHNR), an interdisciplinary group of leaders across key federal agencies, to identify sustainable diets as a research priority in the creation of its 2016-2021 National Nutrition Research Roadmap. And though interest in this topic continues to grow, there is evidence that federal funding remains woefully inadequate to support independent research on sustainable diets and food systems.
2. How could more socially and economically sustainable food systems support healthy eating?
While environmental sustainability receives a lot of attention, a truly sustainable diet also takes into account the social and economic conditions that can threaten our health, wellbeing, and the future of our food supply.
Among these considerations are the persistent health and economic disparities embedded in the current US food system, which disproportionately affect Black, Indigenous, and other resilient communities of color who have faced decades of racist and discriminatory practices and policies. Even before the pandemic, the people working throughout the US food system—nearly 40 percent of whom are people of color—experienced greater poverty, poorer healthcare access, and higher occupational health hazards relative to the general population. Many of these same populations are also most vulnerable to the environmental consequences of unsustainable food systems, such as climate change, water pollution, and other environmental impacts. The irony should not be lost on anyone that many Indigenous populations have for generations produced food in harmony with ecological systems—a way of living that, in the US and elsewhere, was deeply and violently disrupted by colonization and genocide.
Pervasive exploitation in the food chain can function to make certain foods cheap, while also preventing workers from being able to afford healthy diets themselves. And unfortunately, this isn’t a challenge unique to workers in the food chain. Many US households are already struggling to afford a healthy—let alone sustainable—diet.
So how can research help?
For one, there are an increasing number of studies that are putting dollar signs on healthier and more sustainable diets. Understanding what these diets might cost consumers, and what segments of the population might be unable to afford them, is an important first step in creating policy and programs that can bring healthier and more sustainable eating into reach for more people. Existing research on programs and initiatives such as the Supplemental Nutrition Assistance Program (also known as SNAP), cash assistance programs, or minimum wage increases will also be useful in identifying the best ways to increase consumer purchasing power, particularly among low-income households. Perhaps most importantly, effective community-based participatory research can support community efforts to resist and address the root causes of social and economic disparities, including racism and exploitative economic systems. Organizations like the HEAL Food Alliance, a multi-racial coalition building a national movement to transform food and farming systems, should be looked to as experts and leaders in shaping the goals and objectives of research that will impact the communities they represent.
3. What are the synergies and tradeoffs when you value both public health and sustainability?
Not every food choice that supports health will support sustainability, and vice versa. In fact, as our research shows, if the US population shifted from our current diet to a healthier diet, greenhouse gas emissions, energy use, and water use could actually increase. This is due in part to the fact that many fruits and vegetables—which most of us don’t eat nearly enough of—are produced in ways that require a lot of water and energy.
Another commonly cited example is the conflict between US dietary recommendations for fish and shellfish and the ability of fisheries to meet this demand in a sustainable way—an issue highlighted by experts in a National Academies of Science workshop and the 2015 Dietary Guidelines Advisory Committee.
None of this is to say that we should abandon our efforts to eat healthfully. Rather, it’s to say that we need to do some problem-solving if we want to eat in ways that are healthy and sustainable for people and the planet, and research can play a key role in helping us get there.
Solving the sustainable food Rubik’s cube
It was more than thirty years ago that federal policy established the first specific directives for prioritizing nutrition research, yet its funding has remained stagnant for decades and coordination across federal agencies remains inconsistent. Meanwhile, many complex factors are fueling the public health challenges embedded in the US food system: rates of diet-related disease and health disparities continue to climb, the degradation of soil and other natural resources has grown more dire, many workers are still underpaid and unsafe, and climate change is now a reality that looms large in our daily lives.
It’s time for the next generation of nutrition research. To fill these gaps in research and provide information we need to make the best possible policy decisions, we must invest in research that is systems-oriented and can help identify healthy diets that deliver the best possible social, economic, and environmental benefits for all populations. Such research must span disciplines, take leadership from communities most affected by health disparities and environmental injustices, and at its core focus on tackling root causes of the greatest threats facing the food system, including the systemic exploitation of people and finite resources.
President Biden’s administration has no shortage of opportunities to prioritize this area of research, which sits at the nexus of some of its foremost policy priorities. US Department of Agriculture Secretary Vilsack is well positioned to play a powerful role in lifting up and improving coordination of nutrition research needs, particularly as he works to rebuild capacity in the department’s research arms. And Congress, for its part, can leverage legislative opportunities such as appropriations and the potential reauthorization of child nutrition programs to ensure that funding is finally available to answer these and other critical nutrition research questions.
Support from UCS members make work like this possible. Will you join us? Help UCS advance independent science for a healthy environment and a safer world.