Rising food accessibility contributed to the increasing dietary diversity in rural and urban China

China has undergone a dramatic transition in food consumption in the past few decades. Diet composition has changed significantly because of an increase in food accessibility and lifestyle changes. To investigate dietary changes in China from the perspective of dietary diversity, we assessed the trend of dietary diversity in China by using the following 4 indicators: count index, dietary diversity score, entropy, and Simpson index. Data of 24,542 adults (age >=18 y) were obtained from the China Health and Nutrition Survey (CHNS) conducted in 2004, 2006, 2009, and 2011. Furthermore, the association between dietary diversity and the number of food facilities was investigated using multivariable regression and local polynomial regression. Results indicate that dietary diversity increased over time and was unequally distributed among regions and families. Urban residents had a significantly more diverse diet compared with their rural counterparts (p<0.01). Moreover, dietary diversity was positively associated with food accessibility (p<0.01), and it was affected by socioeconomic factors such as the family income, household size, gender, age, education, and region. Taken together, these data suggest that the increase in dietary diversity in China in the past decade can be partially attributed to the increase in food accessibility.