Americans enjoy a diverse abundance of low-cost food, spending a mere 10% of disposable income on food.1 However, store prices do not reflect the external costs —economic, social, and environmental—that impact the sustainability of the food system. Considering the full life cycle of the U.S. food system illuminates the connection between consumption behaviors and production practices.
The Food System Life Cycle
Patterns of Use
- Farmers account for 1% of the population, and the average age of farmers is leveling off in the mid-50s after a rapid increase.2,3
- Large-scale family farms account for only 2% of all farms, but 35% of production. Small-scale family farms account for only 26% of production, but represent 90% of U.S. farms.4
- Just 14.8¢ of every dollar spent on food in 2016 went back to the farm; in 1975, it was 40¢.5,6
- In 2012, farmers were reliant on income sources outside the farm to make up 80% of their household income, on average.2
- In 2013-2014, 47% of the hired agricultural labor force lacked authorization to work in the United States.7
- From 1992 to 2012, total cropland decreased from 460 million acres to 392 million acres.8
- Many parts of the U.S., including agricultural regions, are experiencing increasing groundwater depletion (withdrawal exceeds recharge rate).9 In 2013, 88.5 million acre-feet of water were used for irrigation—more than 520,000 gallons per acre; groundwater sources supplied more than half this amount.10
- Nutrient runoff from the upper agricultural regions of the Mississippi River creates a hypoxic “dead zone” in the Gulf of Mexico. 2017 hypoxic dead zone was the largest measured since 1985, at 8,776 sq mi.11
- Although pesticide use declined 1.4% annually from 1996 to 2007, herbicide use increased significantly during the same period.12 In 2008, the U.S. agriculture sector used 516 million pounds of pesticides.13
- Decreased pesticide use is due in part to widespread deployment of genetically engineered crops.13 Less than 20% of corn and soy plants were genetically engineered in 1996; by 2018, 92% of corn and 94% of soybeans were genetically modified.14,15
- In 2012, 1.67 billion tons of topsoil were lost to erosion, equal to about 190,000 tons each hour.16
- Agriculture was responsible for 8.6% of total U.S. greenhouse gas emissions in 2016. Livestock and soil management are major contributors.17
- In 2010, the U.S. food supply provided 4,000 calories per person per day.19 Accounting for waste, the average American consumed 2,476 calories per day in 2010, an increase of 22% from 1970.20
- In 2015, 194 lbs of meat per person were available for consumption, up 23 lbs from 1965. Although red meat consumption declined almost 30% since 1970s, chicken consumption increased steadily.21
- 32% of grains grown are used to feed animals, down from 50%+ in past years.22
- The average American consumes about 22.5 teaspoons of added sugars and sweeteners per day; the American Heart Association recommends between 6 and 9 teaspoons daily for an average adult.20,23
- More than 70% of U.S. adults are overweight or obese (body mass index 25+), and 17% of children age 2-19 are obese.24,25
- Diet contributes to heart disease, certain cancers, and stroke—leading causes of U.S. deaths.24,26
- An estimated 21% of the edible food available is wasted at the consumer level, 50% more than in 1970.27,28 This waste accounts for roughly 15% of the municipal solid waste stream and represents a loss of $450 per person each year.28,29 One estimate suggests that 2% of total annual energy use in the U.S. is used to produce food that is later wasted.30
Material Flow in the U.S. Food System18
(1995, flows in million pounds)
Life Cycle Impacts
The energy used by a system is often a useful indicator of its sustainability. Food-related energy use accounts for nearly 16% of the national energy budget.31 Modern agriculture and the food system as a whole have developed a strong dependence on fossil energy; 13 units of (primarily) fossil energy are input for every unit of food energy availbale.18,19,20,31,32
- Food production impacts of US self-selected diets amount to 4.7 kgCO2 eq. and 25.2 MJ non-renewable energy demand per person per day.33
- Reliance on fossil fuel inputs makes the food system increasingly vulnerable to oil price fluctuations.18
- Consolidation of farms, food processing operations, and distribution warehouses often increases distance between food sources and consumers.18
Consolidation in the food system is also concentrating management decisions into fewer hands. For example:
- Four firms control 85% of the beef packing market; 82% of soybean processing is controlled by 4 firms.34,35
- The top four food retailers sold 45% of America’s food in 2016, compared to only 17% in 1993.36
Energy Flow in the U.S. Food System18,19,20,31,32
Solutions and Sustainable Alternatives
Fresh produce eaten in the Midwest travels an average of more than 1,500 miles. A study by the Leopold Center showed that increasing Iowa’s consumption of regionally grown fresh produce by only 10% would save more than 300,000 gallons of transportation fuel per year.37 Community Supported Agriculture (CSAs) and Farmers Markets are both great ways to support a local food system.
Eat Less Meat
A meat-based diet (28% calories from animal products) uses twice as much energy to produce as a vegetarian diet.18 Meat production as it is widely practiced today also has significant environmental impacts on land use, water use and water pollution, and air emissions.38 20% of Americans cause half of the food-related GHG emissions; a diet shift away from meat could reduce this.33
Organic farms don’t use chemicals that require large amounts of energy to produce, pollute the soil and water, and present human health impacts. Sales of organic food in 2017 were 6.4% higher than in 2016; organic food now accounts for 5.5% of all food sold in the U.S.39
Use Less Refrigeration
Home refrigeration accounts for 13% of all energy consumed by our food system.18 Today’s convenience foods rely heavily on refrigeration for preservation. Consider a smaller, more efficient refrigerator and buying smaller quantities of fresh produce more frequently. Refrigerator efficiency more than doubled from 1977 to 1997, but increases in size have largely offset this improvement.18
Much of household food waste is due to spoilage. Prevent food from going bad by buying smaller amounts; planning meals and sticking to shopping lists; and freezing, canning, or preserving extra produce.40 Many foods that are still safe are thrown out due to confusion about “sell-by” and “use-by” dates.41 For further information on food product dating, see the USDA’s Food Safety and Inspection Service.
- U.S. Department of Agriculture (USDA), Economic Research Service (ERS) (2016) “Food CPI, Prices and Expenditures: Food Expenditures by Families and Individuals as a Share of Disposable Personal Income.”
- USDA (2014) 2012 Census of Agriculture. United States Summary and State Data. Volume 1, Geographic Area Series, Part 51.
- U.S. Census Bureau (2012) “Population Estimates, Detailed Tables.”
- USDA (2014) Structure and Finances of U.S. Farms, Family Farm Report, 2014 Edition.
- USDA, ERS (2018) “Food Dollar Series.”
- Elitzak, H. (1999) Food Cost Review, 1950-97. USDA, Agricultural Economic Report 780.
- U.S. Department of Labor (2016) Findings from the National Agricultural Worker Survey 2013-2014.
- USDA, ERS (2017) “Cropland, 1945-2012, by State.”
- Konikow, L. (2013) Groundwater depletion in the United States (1900-2008). U.S. Geological Survey (USGS) Scientific Investigations Report.
- USDA (2014) 2012 Census of Agriculture: Farm and Ranch Irrigation Survey 2013.
- National Oceanic and Atmospheric Administration (NOAA) (2017) “Gulf of Mexico ‘Dead Zone’ is the Largest ever Measured.”
- Osteen, C., et al. (2012) Agricultural Resources and Environmental Indicators, 2012. USDA ERS.
- USDA (2014) Pesticide Use in U.S. Agriculture: 21 Selected Crops 1960-2008.
- USDA, ERS (2012) “Adoption of Genetically Engineered Crops in the U.S.”
- USDA (2018) “Recent Trends in GE Adoption.”
- USDA, National Resources Conservation Services (2015) National Resources Inventory 2012.
- U.S. Environmental Protection Agency (EPA) (2018) Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990 - 2016.
- Heller, M. and G. Keoleian (2000) Life Cycle-Based Sustainability Indicators for Assessment of the U.S. Food System, The University of Michigan Center for Sustainable Systems, CSS00-04.
- USDA, ERS (2015) “Data Sets: Nutrient Availability.”
- USDA, ERS (2017) “Loss-Adjusted Food Availability.”
- USDA, ERS (2017) “Food Availablity.”
- USDA, ERS (2017) “Feed Grains: Yearbook Tables.”
- American Heart Association (2016) “Sugar 101.”
- U.S. Department of Health and Human Services, Centers for Disease Control and Prevention (2016) “Health, United States, 2015.”
- Ogden, C., et al (2012) “Prevalence of obesity and trends in body nass index among U.S. children and adolescents, 1999-2010.” Journal of the American Medical Association, 307(5): 483-490.
- Harvard T.H. Chan, School of Public Health (2016) “What Should I Eat: Vegetables and Fruits.”
- Buzby, J., et al. (2014) The Estimated Amount, Value, and Calories of Postharvest Food Losses at the Retail and Consumer Levels in the United States. EIB-121, USDA, Economic Research Service.
- Natural Resource Defense Council (2017) Wasted How America Is Losing Up to 40 Percent of Its Food from Farm to Fork to Landfill.
- U.S. EPA (2018) Advancing Sustainable Materials Management: Tables and Figures 2015.
- Cuellar, A. and M. Webber (2010) “Wasted food, wasted energy: The embedded energy in food waste in the United States.” Environmental Science & Technology, 44(16): 6464-69.
- Canning, P., et al. (2010) Energy Use in the U.S. Food System. USDA, ERS.
- Population Division, U.S. Census Bureau (2002) National Population Estimates.
- Heller, M., et al. (2018) “Greenhouse gas emissions and energy use associated with production of individual self-selected U.S. diets.” Environmental Research Letters 13(4):1-11.
- USDA, ERS (2013) “Processing & Marketing: Manufacturing.”
- U.S. Census Bureau (2007) “Share of Value of Shipments Accounted for by the 4, 8, 20, and 50 Largest Companies for Industries.” 2007 Economic Census.
- USDA, ERS (2018) “Retail Trends.”
- Leopold Center for Sustainable Agriculture (2001) Food, fuel, and Freeways: An Iowa perspective on how far food travels, fuel usage, and greenhouse gas emissions.
- U.S. EPA (2012) “Potential Environmental Impacts of Animal Feeding Operations.”
- Organic Trade Association (2018) “Maturing U.S. organic sector sees steady growth of 6.4 percent in 2017.”
- U.S. EPA (2017) “Reducing Wasted Food At Home.”
- USDA, ERS (2016) “Food Product Dating”