Diet shift: Considering environment, health and food culture.

Most studies have suggested that dietary choices have effects on both the environment and human health; however, they have ignored food culture, which is both an "independent variable" and a "dependent variable" of diet choice. The purpose of this study is to explore a diet optimization path that meets nutritional needs and has little impact on the environment, while respecting the local food culture to a large extent. We took China's Xinjiang Uygur autonomous region (hereinafter referred to as "Xinjiang") as the case area because Xinjiang is a multiethnic region with a unique food culture characterized by a high proportion of mutton in meat. According to the study's calculation, the current diet in Xinjiang has a high carbon footprint (CF), water footprint (WF) and ecological footprint (EF) and does not present the nutritional structure of a balanced diet. Considering the trade-offs among environmental carrying capacity, health and food culture is the challenge of changing the local food structure. With the method of multi-objective optimization, we propose "optimal diets", which show potential for mitigating environmental impacts and improving the state of health. Most importantly, one of the optimized diets is most desirable because it considers the preservation of the existing food culture. This study demonstrates the feasibility of providing a route for diet transformation that has double benefits regarding the environment and health, or even triple benefits regarding the environment, health and cultural acceptability.