Understanding Sustainable Diets: A Descriptive Analysis of the Determinants and Processes That Influence Diets and Their Impact on Health, Food Security, and Environmental Sustainability¹,²,³

The confluence of population, economic development, and environmental pressures resulting from increased globalization and industrialization reveal an increasingly resource-constrained world in which predictions point to the need to do more with less and in a “better” way. The concept of sustainable diets presents an opportunity to successfully advance commitments to sustainable development and the elimination of poverty, food and nutrition insecurity, and poor health outcomes. This study examines the determinants of sustainable diets, offers a descriptive analysis of these areas, and presents a causal model and framework from which to build. The major determinants of sustainable diets fall into 5 categories: 1) agriculture, 2) health, 3) sociocultural, 4) environmental, and 5) socioeconomic. When factors or processes are changed in 1 determinant category, such changes affect other determinant categories and, in turn, the level of “sustainability” of a diet. The complex web of determinants of sustainable diets makes it challenging for policymakers to understand the benefits and considerations for promoting, processing, and consuming such diets. To advance this work, better measurements and indicators must be developed to assess the impact of the various determinants on the sustainability of a diet and the tradeoffs associated with any recommendations aimed at increasing the sustainability of our food system.

The Chicago Council⁸ found in its study, Bringing Agriculture to the Table, that diet-related noncommunicable diseases are on track to rise by 15% by 2020 if current trends in the global commercialization of processed foods continue to be overconsumed by an increasingly less active global population (1). Currently, the global food system is estimated to contribute to 30% of global greenhouse gas emissions (GHGEs). With the global population expected to rise to 9 billion or more people by 2050, the Foresight Project⁹ found that rising demand to transport, store, and consume the most resource-intensive food types (namely dairy and meat) in developing economies will further increase the contributions of food and agriculture to environmental degradation and climate change (4). At the same time, the Livewell Project¹⁰ found that UK diets could in fact be rebalanced in line with the government’s dietary guidelines (the Eatwell Plate) to achieve GHGE targets for 2020 by substantially reducing meat and dairy consumption (19). However, looking to GHGE targets for 2050, researchers noted that changes would be needed in both food production and consumption to reach these longer-term targets (7). Recent analysis of the new Nordic Diet found that improvements in GHGEs and other environmental wins could be achieved by improving production, reducing transportation, and changing food types (20). Similar recommendations followed an analysis of dietary shifts in France (21).