Prevalence and geographic distribution of childhood obesity in China in 2005.

China now joins the world epidemic of childhood obesity. Because of the large disparity of environmental conditions across various sub-populations, accurate prevalence of obesity/overweight cannot be estimated by population-based approaches. Using a resident-based targeted approach, we determined the geographical distribution of childhood obesity in China and analyzed the specific factors related to the increasing prevalence of obesity in each of its ten regions. An alarming increase in the prevalence of obesity has spread all over China, except for the poverty western rural areas. In 2005, the prevalence of combined childhood overweight and obesity in China reached 32.5% for males and 17.6% for females in the northern coastal big cities, suggesting that the obesity prevalence in some urban Chinese populations has approached that of the developed countries. The prevalence of obesity in the affluent rural sub-populations first exceeded that in some urban populations; then, as they learned their lessons and revised their lifestyles, the prevalence declined to a lower level approaching that of the transitional societies of other countries. The geographical distribution of obesity prevalence in China is mainly caused by the large disparity in the socioeconomic status related to dietary and lifestyle changes in modern China. Multiple and integrated interventions are urgently needed to halt the epidemic of childhood obesity by tackling its basic causes such as fast food, automobiles, television and lack of exercise. The differing prevalences in different regions of China offer an opportunity to reverse this alarming, growing epidemic of childhood obesity in the world's most populous country.