The Road to Healthier Diet: Benefits of the “Five Vertical and Seven Horizontal” National Trunk Highway System in China

Billions of people worldwide still lack access to healthy diets, with a high concentration in rural areas of developing countries. This paper examines how major transportation investments can improve dietary quality among rural households, leveraging the staggered rollout of the “Five Vertical and Seven Horizontal” National Trunk Highway System (5V7H), the country’s largest expressway network completed by 2007. Using a staggered difference-in-differences design, we find that the 5V7H access increases the Dietary Diversity Score (DDS) and Chinese Healthy Eating Index (CHEI) of rural residents by 0.326 and 2.197 points, respectively. These benefits are more prominent among households with more children, access to refrigerators, or meal preparers with better nutrition knowledge, and less so among households with more diversified agricultural production. We further show that the 5V7H connection improves rural residents’ dietary quality primarily through demand-side channels, including promoting off-farm employment, raising household income, and enhancing dietary literacy. In contrast, the contributions of supply-side channels, such as improved market access or lower food prices, are modest. Overall, our findings highlight the benefits of large-scale transportation infrastructure in facilitating the transition to healthier diets in rural areas of developing countries.