The Increasing Prevalence of Overweight and Obesity of Children and Youth in China, 1989–2009: An Age–Period–Cohort Analysis

Abstract

As childhood overweight and obesity, especially its cohort component, can be viewed as the leading edge of future changes in the population prevalence of obesity, scholars are concerned about what temporal effects drive the rise of childhood overweight/obesity prevalence worldwide. Using eight waves of the China Health and Nutrition Survey from 1989 to 2009, this research conducts hierarchical age–period–cohort analyses to investigate temporal patterns of the rising overweight/obesity prevalence for children and youth aged 2–25 in the world’s most populous country. We find that the age trajectory of overweight/obesity reaches a nadir around age 14 and 15 and increases afterwards. Children and youth are more likely to be overweight/obese in the most recent period of observation, and this pattern is persistent across different socio-demographic groups. Moreover, a statistically significant cohort component is detected for the overall population and further analyses reveal that this cohort increase is mainly restricted to males. Demonstrating distinct age, period, and cohort components embedded in the rise of childhood overweight/obesity in China, this research lends support to the global epidemic of obesity and calls attention to a new phase of the Epidemiologic Transition in China.