Traffic infrastructure and dietary quality improvement: Evidence from Chinese expressway

This paper examines the impact of expressway development in China on enhancing dietary quality among residents and explores its operating mechanisms. Theoretically, expressway is posited to improve dietary quality by augmenting residents’ income and optimizing local market accessibility. Empirically, we utilize dietary consumption data from the China Health and Nutrition Survey spanning 12 regions from 1997 to 2011 to estimate dietary quality among Chinese residents. Meanwhile, we integrate provincial expressway data to investigate the effect of expressway on dietary quality. Findings indicate that expressway development significantly improves the dietary quality of residents, primarily through increasing income and market accessibility. Heterogeneity analysis reveals that the influence of expressway on dietary quality varies across urban and rural areas, different income brackets, and diverse dietary patterns. Expressway has a larger effect on urban, middle-and high-income households, and those with a more balanced diet, compared to rural, low-income households, and individuals with less balanced diets. Specifically, general roads, social insurance, and dietary awareness help to promote dietary improvement effect from expressway among rural, low-income households, and individuals with less balanced diets, respectively. This research contributes novel theoretical insights that facilitate dietary structures transformation among Chinese residents.