Analysis of dietary trends in Chinese adolescents from 1991 to 2011.

BACKGROUND AND OBJECTIVES: To examine temporal trends in dietary energy, fat, carbohydrate, protein, sodium and potassium intake of Chinese adolescents aged 12 - 17 years by sex and urbanicity, using data from the China Health and Nutrition Survey.

METHODS AND STUDY DESIGN: Individual level, consecutive 3 - day 24-hour recalls were analyzed from survey years 1991 (n=504), 2000 (n=665), and 2011 (n=267) from nine provinces representing a range of geography, economic development, and health indicators in China. Linear multivariable regression models were conducted to predict mean intakes of energy, macronutrients, sodium, and potassium. Models were adjusted for age, per capita income, parental education, region, and family size.

RESULTS: From 1991 to 2011, total energy consumption decreased among both sexes and all urbanicity groups (p<0.05). Sodium intake decreased in all sex and urbanicity groups except the high urbanicity group, which was the only group to show significant change in potassium intake (p<0.05). Sodium-potassium ratios decreased overall and across both sexes (p<0.05). However, the major observed shift was a structural change from carbohydrates to fat and protein. Both sexes showed decrease in carbohydrate-derived energy (p<0.05). Proportion of fat-derived energy increased in female adolescents. Proportion of protein-derived energy increased in male adolescents, as well as in the low and high urbanicity groups (p<0.01).

CONCLUSIONS: This suggests Chinese adolescents are transitioning to a low carbohydrate diet. Urbanicity appears to play a role in sodium, potassium and protein intake. Improvements of sodiumpotassium ratios are primarily due to decreased sodium intake and require further reduction efforts.