The Rising Overweight Epidemic in China: An Age-Period-Cohort Analysis, 1989-2009

Qiang Fu, Duke University
Kenneth C. Land, Duke University

Using eight successive waves of the China Health and Nutrition Survey dataset, this paper estimates hierarchical age-period-cohort models (HAPC) to investigate the prevalence of overweight individuals in the population ages 2 to 60. We find that the prevalence of overweight declines from early childhood to adolescence and then increases through the adult ages until the early 50s after which the age trajectory again declines. The period effects are very strong with a virtually monotonic increase in overweight from 1989 to 2009. Furthermore, cohorts born in the early 1950s before China’s great famine (from the spring of 1959 to the end of 1961) are less likely to be overweight, whereas cohorts born in the 15 years after the great famine tend to be overweight. Since 1975, the cohort effects have decreased, with some fluctuations. Finally, we find evidence of sex, regional, and income disparities in the age, period and cohort effects.