Climate change and U.S. consumer food choices

Background: Climate change is altering the growing conditions under which agricultural crops are produced, putting at risk our ability to grow enough high quality food now and for future generations. At the same time, the production, processing, transportation, distribution, and sale of food causes greenhouse gas emissions (GHGEs) that contribute to climate change. Consumers may be able to alter their food choices to mitigate GHGEs caused by the food system. However, little is known about the carbon footprint of food choices in the U.S. or consumer interest in mitigating GHGs caused by the food system. Therefore, the objective of this research is to determine if there are GHGE mitigation opportunities through changes in U.S. consumer food choices and to assess consumer responses to climate driven quality changes in foods and beverages.;Methods: This project used a variety of methods, including economic input-output life cycle assessment, stated preference valuation, ordinary least squares linear regression, multinomial logistic regression, and hedonic sensory evaluation using both primary and secondary data sources. Objective 1 was to estimate the life cycle greenhouse gas emissions (GHGEs) caused by U.S. household food expenditures using data collected from the National Household Food Acquisition and Purchase Survey and to assess association between GHGEs and household sociodemographics. Objective 2 used data generated in Objective 1 to determine if lower spending on meat by U.S. households is associated with reduced GHGEs, improved nutritional quality, greater accordance with the 2010 Dietary Guidelines for Americans, and lower food costs. Objective 3 assessed consumer responses to climate driven quality changes in brewed green tea and quantified consumer willingness to pay for climate mitigation in tea production and other product attributes such as environmental sustainability in production, nutrition, and ethical production attributes.;Results: U.S. household food expenditures accounted for 6.8% of total U.S. GHGEs in 2013. The majority of GHGEs come from the purchase of meat and animal products and are generated at the agricultural stage of the food supply chain. More highly educated and white households generated more emissions from food expenditures compared to non-white households and those with lower educational attainment. Households purchasing less meat as a share of total food spending generated lower GHGEs, spent less on food, and purchased significantly lower amounts of unhealthy macronutrients and of some essential micronutrients per average U.S. adult. Among a sample of U.S. tea consumers there is significant interest for protecting the quality of consumable food and beverage products from the adverse impacts of climate change and for lowering GHGEs in agricultural production. Implications: U.S. food expenditures generate a significant share of total U.S. emissions. Reduced purchase of meats in the U.S. can help to mitigate GHGEs from the food supply chain while simultaneously helping U.S. consumers potentially improve the nutritional quality of their diets and lower food costs. However, U.S. consumers may need nutritional guidance when switching away from meat to ensure adequate intakes of select micronutrients. The results here suggest there exists a significant opportunity to market low emissions agricultural practices to U.S. consumers as a means of mitigating GHGEs.