Appetite for Change: A Policy Guide to Reducing Greenhouse Gas Emissions of U.S. Diets by 2030
Americans consume more meat than almost any other country, and our beef consumption is four times the global average.1 Those meat-heavy diets are threatening the planet. Food production is a major contributor to the climate crisis, including forests that are clearcut to make space for grazing livestock and feed crops, methane from burping cows, emissions created by farm equipment and fossil fuels burned to ship food around the world.
Globally as much as 29% of planet-warming greenhouse gas (GHG) emissions come from food production each year, and more than half of those come from meat and dairy. 2 The livestock sector alone accounts for 16.5% of global greenhouse gas emissions, representing a significant burden on the climate from within the food system.3 Beyond the climate impacts, meat and dairy production, including grazing and agricultural lands producing cattle feed, take up an astounding 30% of the Earth’s surface and 80% of all agricultural land in the United States. 4, 5 This has an enormous effect on biodiversity, as well as on climate change and our ability to mitigate and adapt to the climate crisis.
The Intergovernmental Panel on Climate Change (IPCC) has determined that we have fewer than 10 years to reduce global emissions by half to avoid the worst impacts of catastrophic climate change. To tackle this urgent need, we must align food policy with climate policy and drastically reduce the amount of meat and dairy produced. This is especially true for countries with high consumption, like the United States.
For this report scientists at the University of Michigan and Tulane University, supported by the Center for Biological Diversity, examined the projected climate impact of different dietary scenarios to 2030.
Key Finding: Cutting 90% of beef consumption and replacing 50% of other animal-based foods with plant-based foods in the United States would save more than 2 billion tons of greenhouse gas emissions from being released into our atmosphere by 2030 — the rough equivalent of taking nearly half the world’s cars off the roads for a year.6
Recommendation: U.S. policymakers at federal, state and municipal levels should take immediate steps to accelerate the reduction of beef consumption by 90% and reduce all other animal products by 50% as part of their efforts to address climate change. This policy guide serves to support these steps and outline a number of programs that can be undertaken at all levels of government, with key recommendations for decision-makers at municipal and federal levels. Among the specific recommendations are changes to government purchasing practices and nutrition education to support fewer animal-based products and more plant-based foods, as well as ending policies that distort market prices and favor carbon-intensive livestock production.
In its Special Report on Climate Change and Land released in 2019, the Intergovernmental Panel on Climate Change (IPCC) warned that food systems are already being adversely affected by the frequency and intensity of extremes associated with climate disruption. Declining crop yields, unpredictable planting seasons, increases in agricultural pests and diseases, and worsening land degradation pose a threat to food security.7
But it isn’t just climate change that’s affecting food security. Our current food system is creating a downward spiral in which unsustainable production contributes to climate change, poor soil health and desertification, excessive water extraction, pollution and biodiversity loss. And all of this makes it increasingly difficult to continue producing enough nourishing, healthy food.
Meat and dairy production have a disproportionate impact on our food system.8 Globally more than 16% of total yearly planet-warming emissions come from livestock.9 And beef makes up the most significant part of that: Emissions from cattle contribute 65% of the total from the livestock industry.10
The evidence is overwhelming that shifting from high levels of meat and dairy consumption — such as those in the average U.S. diet — toward plant-forward diets can help reduce food-related greenhouse gas emissions. In fact several studies have determined that we won’t be able to meet international climate targets without reducing consumption of animal-based foods and shifting toward diets higher in plant-based foods.11, 12, 13
If global greenhouse gas emissions aren’t halved within the next 10 years, humans and wildlife alike will suffer the effects of catastrophic climate change.14, 15
Newly released research projecting the emissions created by different diet scenarios in 2030 shows that the cost of inaction, or policies that promote livestock production, will continue to increase emissions, while taking action to decrease consumption of animal-based foods can bring us closer to the necessary reductions to meet climate targets.16
By integrating food policy into climate policy with a focus on reducing meat and dairy consumption and production, leaders can decrease diet-related emissions, increase food security and improve public health. There are also significant co-benefits to ecosystems and wildlife, since livestock production is a leading cause of deforestation, overuse of water, pollution and biodiversity loss.
The Case for Food Policy as Climate Policy
Recent research overwhelmingly acknowledges the high greenhouse gas emissions-intensity of meat production relative to other foods and the opportunity for dietary shifts to reduce food-related greenhouse gas emissions.17 One study in the European Union, for example, revealed that halving the consumption of meat, dairy products and eggs would achieve a 40% reduction in nitrogen emissions, 25% to 40% reduction in greenhouse gas emissions and 23% less per capita use of cropland for food production.18 Policies that can advance these types of widespread dietary shifts are an important tool for reducing total greenhouse gas emissions.
Supporting the literature on dietary shifts, multiple global studies explore the relationship between the agricultural sector, various individual food products and greenhouse gas emissions generally, and conclude that animal products, specifically ruminant meat, account for the most emissions of all food products in middle and high income countries.19, 20 Beef production produces 5 times more greenhouse gas than the average of the other livestock categories.21
In the United States, meat production accounts for 56.6% of total greenhouse gas emissions in all diets and 595,514 metric tons CO2eq per day. Within the meat group in American diets, 80.6% of greenhouse gas emissions come from beef, 9.5% come from poultry, and 8.5% come from pork.22
The greenhouse gas emissions associated with plant-based proteins are significantly smaller than those associated with animal-based products, so replacing meat with foods such as beans, legumes, lentils, nuts, and soy is key to reducing diet-related emissions. Ruminant meats (beef and lamb) have emissions per gram of protein that are about 250 times those of legumes.23 A 2019 study found that ruminant meats were the most greenhouse gas-intensive items by serving, energy content, protein or mass. The researchers found that bovine meat was 316, 115, and 40 times more emissions-intensive than pulses (beans and peas), nuts and seeds, and soy, respectively.24
The consensus among relevant studies is that reducing animal-based products and replacing them with plant-based foods is an effective way to reduce dietary greenhouse gas emissions. Although the complete elimination of animal-based foods may not be needed to achieve the necessary greenhouse gas reductions, a priority should be placed on limiting the consumption and production of high-impact meats like beef.
U.S.-focused studies discuss the relative greenhouse gas intensity of meat and dietary shifts as a mechanism to reduce food-related greenhouse gas emissions. One study found that replacing beef with beans could achieve approximately 46% to 74% of the reductions needed to meet President Barack Obama’s 2020 greenhouse gas emissions reduction target for the United States.25 Another study found that replacing beef in the diets of U.S. individuals with legumes, nuts and seeds would reduce dietary greenhouse gas emissions for these individuals by 40%, improve the nutritional quality of their diets, and reduce their food costs.26
Researchers have also shown that self-selected U.S. diets with the lowest carbon footprints are healthier than those with the highest carbon footprints.27
Many U.S.-focused studies discuss dietary guidelines or related policies as a policy lever for emissions reductions.28 Dietary recommendations that fail to recognize the environmental costs of food production can result in an increase in greenhouse gas emissions. For example, one study found that a shift from the average U.S. diet to the USDA dietary recommendations could result in a 12% increase in diet-related greenhouse gas emissions, primarily from the increase in dairy consumption.29 According to another study, “Given the evidence and the scale of influence of the Dietary Guidelines for Americans on food systems, incorporating sustainability into them should be prioritized.”30
See Appendix A for a list of studies reviewed for this section.
New Study: Implications of Future US Diet Scenarios on GHGs
New research by experts from the Center for Sustainable Systems at University of Michigan and Tulane University examines four hypothetical U.S. dietary patterns to determine how a reduction in the consumption of animal-based foods and a replacement with plant-based foods could affect diet-related greenhouse gas emissions on a per capita and cumulative basis. The scenarios were projected to 2030 and included population growth to estimate the climate impacts associated with different potential courses of action.
Read the complete study on University of Michigan’s Center for Sustainable Systems website.
The researchers used USDA’s Loss Adjusted Food Availability dataset as a proxy for the commodity foods consumed in the current US diet. The greenhouse gas emissions associated with producing those foods were determined using an extensive compilation of life cycle assessment literature.31
The emissions were then calculated for the following scenarios:
- The baseline average U.S. diet, based on data for 2016, remains unchanged to 2030;
- Meat and poultry consumption increase according to USDA projections for 2030;
- Consumption of animal-based foods (red meat, poultry, fish/seafood, eggs, dairy and animal-based fats) decreases by 50% and is substituted with plant-based foods; and
- Same projections as scenario 3, but a decrease in beef consumption of 90% instead of 50%.
The emissions from producing the average U.S. diet are 5.0 kg CO2 equivalent (CO2eq) per person per day, with 80% of total diet-related greenhouse gas emissions from animal-based foods. All animal-based foods account for 82% of total diet-related emissions, with beef responsible for 40% of the total emissions. With USDA-projected increases in meat and poultry consumption (and no changes in consumption of other foods), per capita greenhouse gas emissions would increase to 5.14 kg CO2eq per day in 2030. At this projection 49% of total diet-related emissions would come from meat; 41% of total emissions would come from beef.
The projections significantly change when diets are shifted. Decreasing consumption of animal-based foods by 50% from the baseline would reduce diet-related greenhouse gas emissions by 35% to 3.3. kg CO2eq per person per day. In this scenario 36% of total diet-related emissions would be from meat, with 31% of total emissions from beef.
When beef is further reduced by 90% alongside the 50% reduction for all other animal-based foods, the daily per capita emissions fall to 2.4 kg CO2eq, a 51% decrease from the baseline. With steep reductions in beef consumption, meat is only responsible for 16% of total diet-related emissions and beef for 8% of the total emissions.
Cumulatively these changes are even more significant. Replacing 50% of all animal-based foods with plant-based foods leads to an annual emission reduction of 224 million metric tons of CO2eq (MMT) in 2030. That’s the emissions equivalent of taking 47.5 million cars off the road for a year. The cumulative emissions savings between 2016 and 2030 of shifting 50% of animal-based foods in the baseline diet to plant-based foods would be 1,634 MMT. If 90% of beef were replaced with the 50% reduction in all other animal products, the cumulative emissions savings leap to 2,408 MMT.
Shifting U.S. diets to replace half of animal-based foods with plant-based foods has an annual emissions reduction equivalent to the annual emissions from the energy use of 188.5 million homes or 420 coal-fired power plants. By further reducing beef by 90%, those reductions would be equivalent to the annual emissions from powering nearly 278 million homes or 619 coal-fired power plants.32
These comparisons are not intended to imply that addressing diet-related emissions can replace a rapid, just transition to 100% renewable energy, but rather to demonstrate that reducing food system emissions is a necessary component of reaching climate targets by 2030. Dramatic reductions in greenhouse gas emissions must come from all sectors to avoid catastrophic climate change, and sizable reductions are possible through dietary shifts and related food policy.
Recommendation: Policymakers Must Address Food-related GHGs
As the researchers note in Implications of Future U.S. Diet Scenarios on Greenhouse Gas Emissions, dietary changes can result in dramatic greenhouse gas reductions, but it “will require the concerted efforts of policymakers, the food industry and consumers.”
Many people associate diets and other types of consumption with individual choice, but the reality is that those choices are influenced by policies that shape knowledge and cultural norms, affect pricing and drive demand, and determine the availability of different foods.
Individual dietary changes can help shift cultural norms, drive market demand and empower people to get involved in collective action. However, the responsibility for shifting community and national dietary patterns — and thus what types of foods are produced — ultimately falls to policymakers, who must align the policies that shape agricultural prices, food availability and nutrition education with the growing demand and urgent need for fewer animal-based products and more plant-based foods.
Without dietary changes the emissions associated with the average American diet will increase 9% by 2030 due to population growth.33If meat and poultry consumption increase according to USDA projections, dietary greenhouse gas emissions increase even further. Although it is impossible to predict what Americans will actually consume 10 years from now, the USDA estimates future consumption using a number of assumptions to project food availability, such as macroeconomic forecasts, weather, international developments and agricultural and trade policies including those that affect price, such as subsidies.34
These scenarios show the climate cost of inaction, especially government policies that continue to favor livestock production rather than supporting plant-based diets. To avoid these increased diet-related emissions, policymakers need to acknowledge their role in shaping dietary patterns and strive to create policies that transform both mindsets and purchasing to make healthy, sustainable food more widely acceptable, affordable and accessible.
U.S. policymakers should take immediate steps to accelerate the reduction of beef consumption by 90% and all other animal products by 50% as part of their efforts to address climate change.
The Role of Dietary Guidelines in Climate Food Policy
The Dietary Guidelines for Americans form the basis of federal nutrition policy and programs, including providing a framework for health and nutrition education at the local and national level. This directly affects billions of meals served each year in schools, government cafeterias, military bases, prisons, healthcare institutions and through social service programs such as Meals on Wheels. The dietary guidelines determine the health and sustainability of meals served to our most vulnerable citizens as well as influencing food availability, social norms, and nutrition education for the public at large.35
Dietary guidelines can also help identify and encourage food-environment and policy approaches to systematize healthy, sustainable eating rather than solely relying on individual choice. The 2015 Dietary Guidelines Advisory Committee noted: “These approaches have the potential for broad and sustained impact at the population level because they can become incorporated into organizational structures and systems and lead to alterations in sociocultural and societal norms. Both policy and environmental changes can also help reduce disparities by improving access to and availability of healthy food in underserved neighborhoods and communities.”36
In short the dietary guidelines have an enormous influence over creating equitable food choices and policies in the United States and the greenhouse gas emissions associated with U.S. dietary patterns.
Sustainable dietary guidance is critical to food security
The purpose of national dietary guidelines is to promote health and food security. The 2015 Dietary Guidelines Advisory Committee found that diets lower in animal-based foods and higher in plant-based foods are aligned with the best available nutrition science and help ensure access to sufficient, nutritious and safe food for current and future generations, since they require fewer resources and support soil health and resiliency.37
In 2019 the Society for Nutrition Education and Behavior published a position on the importance of including environmental sustainability in dietary guidance, stating that “environmental sustainability should be inherent in dietary guidance, whether working with individuals or groups about their dietary choices or in setting national dietary guidance. Improving the nutritional health of a population is a long-term goal that requires ensuring the long-term sustainability of the food system.”38
Low-carbon diets featured in dietary guidance around the world
Several countries around the world have begun integrating climate concerns and other environmental impacts into their national food recommendations. The official guidelines of Brazil, Germany, Qatar and Sweden include sustainability and emphasize plant-based foods while calling on citizens to limit red meat consumption. Government-supported guidance issued in Estonia, France, the Netherlands, the United Kingdom and by the Nordic Council of Ministries (which includes Denmark, Finland, Iceland, Norway and Sweden) include similar recommendations.39 In 2016 the Chinese Nutrition Society released updated dietary guidelines along with its “Less Meat Less Heat” campaign urging Chinese consumers to cut meat consumption in half from current levels.40
One of the most recent and notable updates to national dietary guidance was the revision to the Canada food guide released in January 2019. While the guide focuses on health, it acknowledges the environmental benefits of diets higher in plant-based foods and lower in animal-based foods. It emphasizes plant-based proteins and replaced dairy with water as the beverage of choice.41 Health Canada made a commitment to develop its latest guidelines based on scientific evidence and free from industry influence, an example the United States should follow.42
Federal Policy Recommendations
1) Incorporate sustainability in the Dietary Guidelines for Americans
The Dietary Guidelines for Americans should acknowledge the connection between diets high in animal-based foods and threats to the climate, environment and food security. These government-issued recommendations should emphasize plant-based foods (including protein), and call for limiting meat and dairy consumption, particularly red meat.
The 2015 Dietary Guidelines Advisory Committee considered sustainability in its review of the latest research on diet and nutrition, leading it to conclude 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.” 43
The body of evidence supporting plant-forward diets for the climate, health and food security has only grown since the 2015 advisory committee released its scientific report.44 But the 2020 Dietary Guidelines Advisory Committee was prohibited from doing a systematic review of the evidence linking sustainability and healthy diets.45 As a result it cannot include sustainability in its nutrition recommendations. But the 2020-2025 Dietary Guidelines for Americans can still include information on the climate impact of food production to educate policymakers, institutional food purchasers and the public.
The Dietary Guidelines for Americans should include recommendations and supporting evidence to help shift the American diet toward a major reduction in beef and substantial reduction in all other animal-based foods from current consumption levels. Following the lead of science-based recommendations in other countries this should include limiting meat consumption, particularly red meat, and replacing it with plant-based foods rather than increased consumption of poultry or seafood. The guidelines should emphasize the importance of plant-based foods, including proteins, and replace dairy with water as the beverage of choice.
Finally, the guidelines should acknowledge the importance of dietary shifts in reducing food-related greenhouse gas emissions as well as other environmental impacts and highlight the alignment of sustainable diets with food security and improved public health. At a minimum the guidelines and related education and outreach should place greater emphasis on plant-forward eating, such as vegan and vegetarian diets, and indicate that these healthy dietary patterns are more environmentally sustainable.
2) Increase the availability of plant-based foods in school lunches
Federal school-meal programs like the National School Lunch Program and the School Breakfast Program serve approximately 30 million children, who eat nearly 5 billion lunches and more than 2.4 billion breakfasts over the course of a school year.46 Many of those meals consist predominantly of meat and dairy products.47
Based on a typical high-school menu, outlined by the Institute of Medicine Committee on Nutrition Standards for National School Lunch and Breakfast Programs, students consume about eight ounces of ground or processed beef weekly.48 Beef-based dishes such as sloppy joes, hamburgers and hotdogs are served three days a week on average. This amounts to 7.7 billion kg CO2eq per school year.49
Dairy milk is offered every day in eight-ounce servings as a key part of the USDA’s school-meal requirements, resulting in more than 2.2 billion kg CO2eq each year.50
The first step to support healthier, climate-friendly school lunches is to reverse the Trump administration rollbacks to the Healthy, Hunger-free Kids Act of 2010. This law set standards for school meals that would make sure kids were receiving more vegetables, fruits and whole-grain rich foods. In a rule proposed January 17, 2020, the USDA would let schools decide how much fruit to offer, what types of vegetables to include in meals. The rule would also broaden the definition of snacks and let schools serve more à la carte meals.51
Rather than making it easier for schools to replace healthy meals with hamburgers and French fries, the USDA should focus on making sure schools have enough access to fresh fruits and vegetables and the appropriate training on how to serve delicious, appealing, plant-based meals.
Second, the USDA should add more plant-based proteins to the USDA Foods list. While plant-based alternatives that meet nutritional guidelines can replace animal-based meat, there are few such options available through USDA Foods.52 Public schools rely on these commodities for 10 to 15 percent of their food purchases.53 For example, many legume varieties are available, but if schools want to serve veggie burgers, tofu, tempeh or plant-based chicken nugget alternatives, they have to source them with limited funds available for commercial purchases, often at a significantly higher cost.54
In addition to improving the availability of cost-effective meat alternatives through USDA, federal policymakers should support legislation that would incentivize plant-based meals with additional funding to help offset the low reimbursement rates for school meals and the costs of plant-based foods that don’t currently enjoy the subsidies granted to meat and dairy production.
Finally, USDA should cover the cost of plant-based milk substitutes. Meals with non-dairy milk substitutions are currently reimbursed at the same rate as meals serving cow’s milk, even though government subsidies and surplus purchases keep the cost of dairy lower than plant-based alternatives. Since the federal government does not reimburse additional costs incurred from offering plant-based milks, many schools cannot afford to broadly offer these alternatives to students.
Fully reimbursing plant-based milks would level the playing field, reduce greenhouse gas emissions associated with school lunches, and be more inclusive to all students. The American Medical Association adopted a resolution at its 2018 Annual Meeting acknowledging that “lactose intolerance is a common and normal condition among many Americans, especially African Americans, Asian Americans, and Native Americans.” The association proposed modifying the National School Lunch Act to eliminate requirements that children produce documentation of a special need in order to receive milk alternatives and that DGAs and other federal nutrition guidelines should clearly indicate that meat and dairy products are optional.55
3) End subsidies and other government funding schemes that encourage overproduction of meat and dairy
In 2018 the livestock industry received $677 million in subsidies, and more than double that if dairy program and animal-feed subsidies are included. Fruits and vegetables received less than $1 million.56 Between 2002 and 2014, U.S. taxpayers lost more than $1 billion due to livestock operators being grossly undercharged for public lands grazing fees.57 The USDA has also spent $47.1 million in taxpayer money to purchase 22 million pounds of surplus cheese since 2016, dumping into school lunches and other government programs.58
These direct and indirect subsidies suppress the price of meat, distort market demand and encourage overproduction. In one of starkest examples of how government policies help prop up failing industries, as of February 2019, the U.S. had an excess of 1.4 billion pounds of cheese.59 Meanwhile, the U.S. doesn’t grow enough vegetables to meet its own federal nutrition recommendations.60
If subsidies were shifted to support sustainable agriculture or if livestock producers had to account for the true environmental, health and social costs of production, meat and dairy would be much more expensive.61
Congress should prohibit programs, including surplus purchases and cash payouts, that distort market demand and incentivize the overproduction of meat and dairy products. The government funding currently supporting feed crops and industrial meat and dairy production should be shifted to support organic and plant-based agriculture for human consumption that produces fewer greenhouse gas emissions and supports climate resilience through improved soil health and biodiversity.
State Policy Recommendations
1) Create a statewide, cross-agency food policy council with clear sustainability goals
State governments are responsible for meeting the demands of federal policies and guiding local policies while managing a variety of state-level food programs and challenges. By working across agencies such as public health, environment and agriculture, a food policy council can ensure that initiatives remain aligned with state health and sustainability goals and that the actions of one department don’t counteract measures being taken in another. Agencies can also use their shared expertise to craft public education campaigns to raise awareness of the climate impact of dietary choices and inform the public about health and other co-benefits of plant-centered diets. Beyond agency staff, the council should include diverse stakeholders to develop innovative ideas, earn broad community support and ensure that those most affected by the food system have a voice at the table.
Measures have been passed in several states to promote local food through a statewide, systemic approach.62 These have included legislative amendments to direct marketing of fresh fruits and vegetables, task forces to investigate ways to encourage residents to purchase local food, commissioned studies to determine barriers to local food purchases, and policies to increase accessibility to healthy food options. A similar approach can be used to advance climate-friendly, plant-forward diets. Food policy councils can play a role in developing and overseeing these types of measures and integrating climate goals into recommendations for meaningful change.
For example, the Washington State Food Policy Forum convenes cross-sector stakeholders to develop recommendations to improve the food system. The forum’s 2019 report addressed key areas such as food insecurity, barriers to small and mid-size farmers accessing markets, and the impacts of climate change.63 The forum could be tasked with creating recommendations for healthy, sustainable dietary patterns and policies that can improve procurement, accessibility and promotion of plant-based foods to help meet state climate targets. (See municipal recommendations for integrating sustainable diets into climate action plans.)
2) Increase the availability of plant-based foods in schools, agencies and state-owned facilities
State-level procurement policies determine food-purchasing decisions for public universities, healthcare facilities, prisons and other state-funded programs. These policies can shift large institutional purchases toward plant-based foods and influence local procurement policies (see municipal recommendations for more information). Specific procurement targets should be set that reduce purchases of beef by 90% and other animal-based foods by 50% while increasing plant-based options.
Procurement policies that require more plant-based foods can be an effective way to shift dietary choices. Simply doubling the proportion of vegetarian meals in university cafeterias increased vegetarian sales by as much as 79%, with the most significant change among diners who previously were least likely to choose the vegetarian option.64
State procurement policies can also ensure that more people have access to plant-based foods, particularly individuals who have little choice about what they get to eat. California SB 1138, passed in 2018, requires licensed healthcare facilities and prisons to make plant-based meals available to the people in their care. The bill recognizes the health benefits of plant-based meals as well as their ability to meet most religious, ethical and food sensitivity concerns.65
Although school meal programs are administered by the USDA (see federal policy recommendations), state policymakers can make it easier for schools to purchase healthier food. Farm to school programs provide funding and change procurement processes to ease access to local food. Salad bars created through these programs have been shown to increase vegetable consumption at schools by as much as 84%.66
Many states provide reimbursements, grants and other additional funding to help schools stretch their limited budgets to improve the quality of school meals.67 Funding for nutritious, healthy meals for kids should be available in every state. Policymakers can go one step further and incentivize plant-based foods and dairy alternatives. A bill introduced in California offers additional per-meal reimbursements for meals that include plant-based options, as well as providing financial aid to meet infrastructure needs for plant-based food preparation and menu changes, such as cafeteria equipment, technical assistance and student engagement.68
3) Increase funding and technical support for farmers’ markets, community gardens and urban agriculture to improve access to fresh fruits and vegetables
Many local and regional food initiatives that increase access to fresh, affordable plant-based foods and build food-system resilience can benefit from state-level support. For example, farmers’ markets are mostly regulated at the state and local levels, which gives state policymakers the opportunity to remove barriers to farmers participating in markets, promote farmers’ markets to residents, and provide guidance to the state’s rules and regulations for farmers and operators.69 State legislatures can provide funds to support development, renovation and maintenance. Finally, state policymakers can help give farmers the resources they need to accept SNAP, WIC and seniors’ nutrition program benefit, which can help increase produce sales.70
Similarly, state policy that makes it easier for people to establish community gardens and urban agriculture projects can revitalize communities and provide additional access to fresh, local produce. This can include allowing gardens in public spaces and in lieu of lawns and allowing sales of the fruits and vegetables grown in these gardens to help them become financially sustainable. By providing information for students and seniors, these projects can also become educational opportunities about food system resilience and climate-friendly diets.
Municipal Policy Recommendations
1) Adopt procurement policies that reduce meat and dairy purchases
Cities have the power to determine how government funds are spent on food in their jurisdictions. These policies can directly affect local markets as well as provide guidance for food service throughout the city and serve as a model for institutional procurement policies. Procurement policies should include specific targets to reduce purchases of animal-based foods by 50%, with a steeper reduction for beef, and to increase purchases of plant-based foods. In addition to greater reductions in diet-related greenhouse gas emissions, limiting red and processed meats also offers health benefits.71
Fourteen cities around the world signed onto the C40 Good Food Cities Declaration at the C40 World Mayors Summit in 2019. The declaration acknowledges food as a leading source of consumption-based emissions and urges mayors to introduce policies that make low-carbon food more affordable and accessible. Among those policies is a pledge to align procurement policies to the Planetary Health Diet, which focuses on vegetables, fruits, whole grains, plant proteins and modest amounts of animal proteins.72
In the United States several cities including Boston, Chicago, Los Angeles and New York have adopted the Good Food Purchasing Program, a framework to align food purchasing with five core values: local economies, valued workforce, environmental sustainability, nutrition and animal welfare.73
The values of the program as a whole, and within the environmental sustainability standards, represent many interconnected issues that are important components of a just transition to a sustainable food system. However, in order to achieve meaningful reductions in food-related greenhouse gas emissions, cities adopting the program will have to not only increase menu options with lower carbon footprints but decrease purchases of high-intensity animal-based options.
2) Increase the availability and acceptance of plant-based options
Local policymakers can also adopt initiatives that help their communities reduce meat and dairy consumption by increasing the availability, affordability and acceptance of plant-based options across towns and cities.
These policies will help raise awareness about the connection between livestock production and climate change and can offer marketing cues at the point of purchase to influence customers’ willingness to choose plant-based options, reduce consumption of animal-based foods, and increase support for government action to curb diet-related greenhouse gas emissions.74
Communities can only shift toward climate-friendly diets if plant-based options are widely available. In 2019 Los Angeles councilmember Paul Koretz introduced a motion directing city facilities and services such as parks, the zoo, and Meals on Wheels to report on currently available vegan options and how they plan to make sure those options are available on an ongoing basis. The motion also explores the feasibility of plant-based food concessionaires in each airport terminal, a minimum of one vegan entrée being available at all other airport restaurants, and a potential future ordinance requiring all large-scale entertainment venues in the city that sell food to provide at least one vegan option.75
Ensuring a minimum of one plant-based entrée is aligned with reducing the carbon footprint of menus, appealing to the growing consumer interest in plant-based foods, and offering more inclusive options as plant-based meals are consistent with a range of religious, ethical and medical dietary restrictions.
Another popular option for increasing the availability and acceptance of plant-based foods is to join the Meatless Monday movement. Meatless Monday was founded in association with the Johns Hopkins Bloomberg School of Public Health to encourage people to cut meat from their diets one day a week for their own health and the health of the planet.76 Green Monday is a similar global effort, started in Asia, that focuses on reducing meat consumption to benefit the climate and food security.77 While replacing meat just one day a week won’t be enough to achieve the necessary reductions in food-related emissions, Meatless or Green Mondays are a great way to introduce people to plant-based foods and begin the cultural shift needed for more ambitious dietary changes.
Meatless or Green Monday resolutions can take a variety of forms, such as adopting Meatless or Green Mondays in government offices, passing official proclamations urging institutions and businesses across cities to participate, and encouraging schools, hospitals and restaurants to feature meatless meals one day a week.78 Participating institutions may choose to serve an entirely meat-free menu on Mondays or actively promote meatless dishes in their cafeterias and on social media. The more these efforts can be widely adopted and promoted, the more effective they will be in raising the profile and social acceptance of plant-based eating.
There are several other barriers to healthy, sustainable eating, such as lack of access to affordable, fresh produce and knowledge gaps around cooking and nutrition, that can be addressed on the local level. Policies that support farmers’ markets and solutions such as no-fee grocery delivery can help make fresh, healthy food more accessible.79 Partnerships between food banks, community gardens, local chefs, healthcare workers and sustainability advocates can help educate diverse audiences on how — and why — to prepare appealing plant-based meals. Transforming diets and local food systems will require this kind of creative, community-based collaboration across sectors.
3) Integrate sustainable diets in climate action plans
Many cities use sector-based greenhouse gas inventories focused primarily on accounting for emissions from energy use within city boundaries and those generated from waste treatment. However, the climate impacts of city policies and activities reach far beyond their borders. By using a consumption-based approach, cities can capture direct and lifecycle greenhouse gas emissions from goods and services consumed by their residents.80
Recognizing the climate contribution of meat and dairy and the mitigation opportunities of dietary shifts in climate action plans can help raise public awareness of the connection between food and climate.81 Through consumption-based accounting and identifying specific steps, climate action plans can move beyond education and individual action to creating a policy environment that supports a climate-friendly local food system.
For example, the climate action plan for the city of Portland and Multnomah County in Oregon includes a section on food and agriculture, with specific timebound actions and lead agencies assigned to their development and implementation. These actions include low-carbon food choices in public and business outreach (including skills development), efforts to encourage plant-based diets, collaborative partnerships to promote low-carbon diets and affordability and access, integration of sustainable food system issues into land-use planning and purchasing policies.82
The difference in cumulative emissions between the scenarios explored in Implications of Future U.S. Diet Scenarios on Greenhouse Gas Emissions demonstrates how policy decisions made today can affect our ability to achieve the necessary emission reductions by 2030.
If meat and dairy consumption continue to rise in the United States, diet-related emissions will push us further away, each year, from the reductions needed to avoid the worst impacts of the climate crisis.
In the study the authors note that the annual emissions reduction associated with decreasing consumption of all animal-based foods by half represents 24% of the reduction from the 2017 emissions required to meet the U.S. Intended Nationally Determined Contribution in the Paris Agreement, with the steeper reductions in beef consumption bringing emissions 36% closer to the U.S. Nationally Determined Contribution.83
Because the U.S. Nationally Determined Contribution is not sufficient to meet the Paris Agreement climate targets, other approaches have estimated an equitable U.S. “fair share” of emissions reductions needed to achieve Paris targets. Using an equity approach based on responsibility and capability, the U.S. fair share of emissions reductions for meeting a 1.5 degree Celsius Paris target equates to cutting U.S. domestic emissions by at least 60 to 70% below 2005 levels by 2030.84 A diet-related reduction of 224 MMT, derived from halving U.S. consumption of all animal-based foods, would represent 5 to 6% of the "fair share" domestic emissions reductions in 2030 from 2016 levels that are consistent with meeting a 1.5 degree Celsius target. By reducing beef consumption by 90% and all other animal-based foods by 50%, diet-related emissions could contribute 8 to 9% of the domestic reductions needed to meet equitable climate targets for the United States.85
These dietary shifts will require ambitious, transformative changes. A 90% decrease in beef from the current average would result in consumption of only four pounds of beef per person per year, or about 16 hamburgers annually. That amounts to one beef burger every three to four weeks, compared to the current consumption of three hamburgers per person every week. Even with plant-based foods becoming increasingly mainstream, achieving the necessary diet-related emissions reductions will require a shift in how American think about their diets.86
This report has outlined a number of pathways governments can take to accelerate the shift from high consumption of animal-based foods toward diets higher in plant-based foods. By bringing together food policy and climate policy, governments can provide a foundation for a healthy, climate-friendly food system.
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17. We reviewed 56 studies that address climate and diet published between 2014 and 2020. Of these, 47 acknowledged the relatively high impact of meat and dairy relative to other foods and 49 mentioned dietary shifts as a mechanism to reduce greenhouse gas emissions. See Appendix A for a list of studies reviewed.
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21. Eshel, G., A. Shepon, T. Makov, and R. Milo. 2014. Land, irrigation water, greenhouse gas, and reactive nitrogen burdens of meat, eggs, and dairy production in the United States. PNAS. 111 (33). Authors found: Producing 1 megacalorie of beef requires ≈ 28, 11, 5, and 6 times the average land, irrigation water, greenhouse gas emissions, and Nr of the other animal categories.
22. Heller, M.C., A. Willits-Smith, R. Meyer, G.A. Keoleian, and D.Rose. 2018. Greenhouse gas emissions and energy use associated with production of individual self- selected US diets. Environmental Research Letters. 3 (4).
23. Tilman, D. and M. Clark. 2014. Global diets link environmental sustainability and human health. Nature. 515: 518-522.
25. Harwatt, H., J. Sabaté, G. Eshel, S. Soret, and W. Ripple. 2017. Substituting beans for beef as a contribution toward US climate change targets. Climatic Change. 143: 261–270.
26. Willits-Smith, A., Aranda, R., Heller, M.C., and Rose, D. 2020. Addressing the carbon footprint, healthfulness, and costs of self-selected diets in the USA: a population-based cross-sectional study. Lancet Planetary Health. 4:e98-106.
27. Rose, D., Heller, M.C., Willits-Smith, A.M., and Meyer, R.J. 2019. Carbon footprint of self-selected US diets: nutritional, demographic, and behavioral correlates. American Journal of Clinical Nutrition. 108:1-9.
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31. Emissions factors used in this study include farm gate production only and do not include processing, transport, retail or at-home contributions.
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49. Equal to 17.05 billion lbs CO2eq, calculated based on 2 ounces of beef served 3 times a week per NIH sample menus to 4.9 billion students participating in National School Lunch Program. 2.9 lbs CO2eq per ounce calculated using following global warming potentials (GWP) (i.e. warming effect relative to CO2 over 100-year period): N2O GWP=298, CH4 GWP=25, hydroflourocarbons GWP=1,430) (Hamerschlag, Kari. “Meat Eater’s Guide: Methodology.” EWG)
50. Equal to 5 billion lbs CO2eq, calculated based on one 8 oz serving of milk served daily to 4.9 billion students participating in National School Lunch Program. 1 lb CO2eq per serving calculated using following global warming potentials (GWP) (i.e. warming effect relative to CO2 over 100-year period): N2O: 298, CH4: 25, hydroflourocarbons: 1,430) (Hamerschlag, Kari. “Meat Eater’s Guide: Methodology.” EWG)
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67. School Meals Legislation and Funding by State. 2019. Food Research & Action Center. Retrieved from: https://frac.org/wp-content/uploads/state_leg_table_scorecard.pdf
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74. Wellesly, L., Happer, C. and Froggatt, A. 2015. Changing Climate, Changing Diets: Pathways to Lower Meat Consumption. Chatham House.
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81. Bailey, Rob, Antony Froggatt, and Laura Wellesley. 2014. Livestock–climate change’s forgotten sector. Chatham House.
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85. U.S. EPA reports 2005 U.S. net emissions at 6577 MMT. Therefore, a 60 to 70% emissions reduction below 2005 levels by 2030 requires U.S. domestic emissions to reach 2631 MMT and 1973 MMT in 2030, respectively, which represents an emissions reduction of 3692 MMT and 4349 MMT below a projected 2030 baseline of ~6323 MMT. The emission savings from diet scenarios 3 (224 MMT) represents 5 to 6% of the required emissions reductions in 2030 to meet a 1.5°C climate target, and the savings from diet scenario 4 (330 MMT) represents 8 to 9% of the required emissions reductions. .The Climate Equity Reference Calculator is available at https://climateequityreference.org/
86. Calculated based on beef per capita availability at current and 90% reduction levels (see Heller 2020, Table 9), converted to quarter-pound hamburgers.