Future foodscape: Impact of population decline and aging on China's dietary carbon footprint and food security

The food system is a major contributor to global climate change, making its decarbonization and sustainable transformation a critical area of academic inquiry. As many countries, including China, experience rapid population aging, new challenges emerge for reducing food-related carbon emissions. Variations in dietary preferences and entrenched eating habits across age groups introduce substantial uncertainty into projections of future dietary carbon footprints. This study analyzes age-specific dietary carbon emissions, simulates the impact of demographic aging on China's food-related emissions, and explores the drivers of dietary transitions. Using microdata from the 2014 China Urban Household Survey, we simulate the effects of demographic changes—both in population size and structure—and potential shifts in dietary behavior. The results indicate that total dietary carbon emissions are likely to peak and then decline around 2030 due to population contraction. However, per capita emissions will increase as the population ages. Health-oriented dietary transitions and technological advancements in agriculture could reduce emissions by approximately 10 %–13 % and 22 %–26 %, respectively. Although the dietary system may face reduced carbon pressure, other systemic risks could arise. Notably, aging may lead to a decline in the agricultural workforce, exacerbating mismatches between labor supply and food demand, and posing additional risks to food security. These findings underscore the need for improved agricultural efficiency, technological innovation, and a carefully coordinated approach to urbanization and rural revitalization strategies.