Agri-food production is necessary to sustain the growing global population, but it adversely impacts the environment in various ways, including climate change, eutrophication, acidification, land and water uses, and loss of biodiversity, etc. These environmental impacts can also negatively affect human health, which could in theory outweigh the health benefits of nutritious food. While better agricultural practices need to be developed and applied to minimize the environmental burdens associated with the production chains, consumers are expected to implement more sustainable lifestyles and eat more environment-friendly foods. Life Cycle Assessment (LCA) is an analytical tool to evaluate the sustainability of a product by examining all the resources used and emissions generated during its life cycle. The first part of this work focused on the upstream production. An LCA of organic blueberry production was conducted to evaluate the trade-off between seasonal and local options and answer the question of whether imported fresh or domestic frozen blueberries are more sustainable. Fresh blueberries from Chile showed superior environmental performance within 2-week storage, due to lower electricity use associated with refrigeration and higher farming yield. Furthermore, length of storage and transportation distance were also found important; if farming yields are comparable, consumption of locally produced, fresh blueberries will be a better choice because of less energy use and shorter transportation distance. The second part of this work targeted at the downstream consumption and aimed to reduce the U.S. environmental footprint through changing adult eating habits. Supplemental functional units were applied in the LCA to incorporate the functions of food to provide nutrition and satiety. With controlled caloric intake, vegetarian diets were found overall more sustainable. However, large possible variations in the environmental impacts of the compared diets were observed due to wide range of nutritional quality of selected foods. Animal products, including meat and dairy especially, and discretionary foods were identified as hotspots in the American diet, that is, reducing the consumption of these foods or deliberately choosing more sustainable alternatives within the same food categories, like chicken and low-fat milk, can significantly improve the sustainability of current American dietary patterns.
Funding
USDA National Institute of Food and Agriculture, Hatch project 1014964.