(P29-049-23) Developing a Diet Quality Index To Understand Secular and Age Trends in Dietary Quality and Habits Among Chinese Children and Adults

Objectives: Diet quality index (DQI) can be used to assess dietary intake relative to dietary guidelines and recommendations for optimal health and nutritional status, but few DQIs are available for children. The purpose of this study is to develop a DQI and evaluate secular and age trends in dietary quality and habits of Chinese children and adults.

Methods: We used data from 42,266 subjects aged 4 and over who participated in 10 rounds of the China Health and Nutrition Survey from 1991-2019. We collected dietary data by using three consecutive 24-hour recalls combined with weighing methods. Based on specific cut points for estimated energy requirements and physical activity levels in children and adults, we developed a 14-component DQI for assessing adequacy (whole grains, vegetables, etc.), appropriate intake (seafood, poultry, etc.) and food items that should be limited (salt, etc.). We used generalized linear regression models to explore the relationship between DQI scores and nutrient intake.

Results: After adjusting for age, sex, urban residency, income, and survey year, DQI scores increased significantly from 37.5 in 1991 to 47.7 in 2019 (p < 0.0001) but remained less than half of the maximum score (110). DQI scores decreased with age, with adolescents (11 – 19 y) scoring highest (43.6) and older adults (60+ y) scoring lowest (40.8) (p < 0.0001), except for children (4 – 10 y, 43.0) who scored lower than adolescents (p < 0.001). Women, urban residents, and high-income groups scored higher than their peers (p < 0.01). DQI scores were significantly associated with intake of most nutrients. For example, a 1-point increase in score was associated with a 0.81 g/day decrease in fat intake (p < 0.001), a 0.059 g/day increase in protein intake (p < 0.001), a 9.55 kcal decrease in total energy intake (p < 0.001), an 84.09 mg/day decrease in sodium intake, and a 4.55 mg/day increase in potassium intake.

Conclusions: The DQI we developed in this study is a good tool for assessing secular and age trends in dietary quality and habits of Chinese children and adults. The quality of diets in China is improving over time, but there are still many people, especially rural residents and low-income groups, who do not meet dietary guidelines well.

Funding Sources: The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institute on Aging (NIA), NIH.