Reducing environmental footprints and promoting health: Optimizing dietary structure in China

This paper aims to identify a dietary structure in China that can enhance people's health while significantly reducing environmental footprints. Aligned with the United Nations Sustainable Development Goals, this study incorporates four essential types of footprints associated with food consumption: land, water, CO2 and CH4 footprints, with particular emphasis on the often-overlooked CH4 footprint, whose warming impact is 25 times greater than that of CO2. Employing the structural decomposition analysis method, we find that, the dietary structure had the most contribution in reducing environmental footprints than those of population size, urbanization rate, and per capita food consumption volume in China after 2018. To assess the environmental impacts of different dietary structures, we set three scenarios: the current dietary structure S0, a developing dietary structure S1, and an optimal dietary structure S2 designed through an optimal model based on the dietary guidelines for Chinese residents (DGCR) 2022. We measure the environmental footprints resulting from residents' dietary structure across the three scenarios for the years 2025 and 2030. The optimal dietary structure in S2, which aligns closely with DGCR 2022, features meat and poultry consumption at 3.59 % and 3.26 % of per capita food consumption volume in 2025 and 2030, cereal and tubers at 20.48 % and 21.20 % and milk and dairy products at 24.47 % and 24.40 % in 2025 and 2030. Comparatively, S2 demonstrates significant reductions in environmental footprints when compared to S0. Specifically, the land, water, CO2 and CH4 footprints caused by residents' food consumption in S2 would drop by 10.50 %, 19.01 %, 14.32 %, 14.32 % respectively in 2025, and by 11.14 %, 19.85 %, 15.27 %, 15.27 % in 2030, respectively. Importantly, the reduced environmental footprints achieved in S2 are >1.8 times greater than those in S1. The findings highlight the potential of the dietary structure in S2 to improve residents' health while concurrently reducing environmental footprints. These results offer a basis for designing effective policies that guide both urban and rural Chinese residents towards healthier and environmentally sustainable dietary choices.