Evaluation On The Sustainability And Shift Potential Of Dietary Structure Of Urban And Rural Residents In Different Regions Of China

Since the Green Revolution,with the continuous improvement of agricultural production technology and the continuous growth of the economy and population,the dietary consumption of Chinese residents has a great change,the change also leads to double challenges for the nutritional safety and environmental effects.Under the circumstance of repeated global COVID-19 pandemic,it is particularly important to systematically clarify the dietary nutrition status,environmental cost,sustainability and shift potential.However,these are still unclear.Therefore,this study adopts the comprehensive nutritional quality evaluation and life cycle evaluation to clarify the dietary nutrition status（macronutrients and micronutrients,comprehensive nutritional quality）and food system greenhouse gas emissions of urban and rural residents in different regions in China;on the other hand,this study quantitatively reveals the sustainability and sustainable shift potential of urban and rural residents’dietary structure in different regions of China.The main results are as follows:（1）The average availability of calories,protein,dietary fiber,vitamin C,vitamin E,potassium,iron,and magnesium for national residents exceed the dietary recommendations.47%and 46%of the national average available calcium and vitamin A were lower than the dietary recommendations,mainly due to lower consumption of dairy products and fruits.The comprehensive nutritional quality evaluation results showed that the national residents’food density richness index（NRF9.3）and nutrient quantity rationality index（FCQRI）were 636 and2.4.The national dietary greenhouse gas emission（DGHG）was 2.1 kg CO₂-eq/day per capita.The availability of various nutrient elements and the comprehensive nutritional quality of urban residents were higher than those in rural areas,and the DGHG was 20%higher than that in rural areas.The residents in the middle and lower reaches of the Yangtze River,North and South China had single and comprehensive quality better than those in the Southwest,Northwest and Northeast China,which are caused by higher consumption of fruits and vegetables,dairy products,and meat.The urban-rural gap of residents in Northwest China,North and Northeast China was larger than that in South and Southwest China,the middle and lower reaches of the Yangtze River in terms of single nutrient,comprehensive quality,and DGHG,which was caused by the larger urban-rural disparity in the consumption of fruits,vegetables,eggs,milk and meat.（2）The average greenhouse gas emission/nutrient density（GHG/NR9）of the national residents’diet was 2.6（>2）,which was unsustainable,due to higher consumption of meat and lower consumption of fruit and dairy products.The dietary GHG/NR9 of urban residents was1.2 times than that of rural residents.The dietary structure of residents in North China,Northeast China,and Southwest China was more sustainable,which might be due to more balanced consumption of fruits,vegetables and meat.The urban-rural gap in dietary GHG/NR9of residents in Northwest China,Northeast and North China was significantly larger than that in South and Southwest China,the middle and lower reaches of the Yangtze River.（3）Optimizing the dietary structure can improve the intake of vitamins and calcium and the comprehensive nutritional quality,while DGHG remains basically unchanged and GHG/NR9was reduced.The main reason was the increase in consumption of dairy products and fruits and vegetables,and the decrease in consumption of meat.The dietary NRF9.3,DGHG,and GHG/NR9 of rural residents increased by 13%,19%,and 8%,the dietary NRF9.3 of urban residents increased by 11%,while DGHG and GHG/NR9 decreased by 4%and 11%,respectively.Optimize the dietary structure to increase the dietary NRF9.3 of residents in all regions,especially the southwest and northwest regions,and reduce the DGHG of residents in South China and the middle and lower reaches of the Yangtze River.Optimizing the dietary structure will reduce the GHG/NR9 in the diets of residents in South and Northwest China,the middle and lower reaches of the Yangtze River.In summary,the nutrient adequacy and insufficiency of Chinese residents coexisted,the calcium and vitamin A deficiency of Chinese residents was relatively serious,and the DGHG exceed the planetary boundary,which was unsustainable.Compared with rural areas and areas with lower economic level,urban residents,residents with higher economic level and better natural endowments had better dietary nutrition quality,higher greenhouse gas emissions,lower sustainability but higher potential for sustainable shift.The agricultural production structure of each region should be adjusted in a targeted manner to realize the sustainable development of the residents’diet.