Food demand and dietary patterns have affected regional and global agricultural production and land use patterns, which in turn affected land use change and forestry activities. With the rapid growth of the population, the current agricultural land is expanding, which seriously threatens the environmental sustainability of the global food and land-use sector. Diets that improve human health and the environment are considered a win-win situation that can lead to co-benefits, reducing diet-related greenhouse gas emissions and land use. In addition, the transition to a sustainable diet requires people in different regions to be able to obtain and afford the necessary food. Particularly, affordability is an important basis for people to switch to a healthier diet in developing regions. Therefore, it is imperative to shift from the current dietary pattern to sustainable patterns that consider environment-health-affordability. Here, we adopt the Model of Agricultural Production and its Impacts on the Environment (MAgPIE) to explore GHG emissions, diet quality, and food expenditure share under four healthy dietary scenarios and a baseline scenario and assess the integrated impact of dietary shifts in different regions. We show that GHG emissions from global agricultural systems remain positive in 2100 if the dietary structure and food demands continue to evolve as currently modeled. Our results underscore that dietary transition is critical to mitigate greenhouse gas and improve diet quality. Furthermore, the price of the food basket would also be lower due to a reduction in aggregate food demand and food waste, thereby alleviating affordability issues, especially for low- and middle-income countries. Overall, the four healthy dietary scenarios all bring benefits to the environment-health-affordability, while trade-offs and synergies between health and affordability can make potential choices for healthy diets vary by region.

sustainability,potential dietary shifts,Environmental-health-affordability,synergies and trade-offs,MAgPIE model