Secular trends in height and weight for healthy Han children aged 0-7 years in China, 1975-2005.

Objective: To report the secular growth changes of Chinese children aged 0-7 years between 1975 and 2005.

Methods: Height and weight measurements obtained from four consecutive national surveys were used to analyze the secular trends. Urban-rural difference and regional difference in growth were compared, respectively.

Results: A rapid positive secular trend was observed in China over the last three decades, increased by 5.3 and 5.0 cm in height for urban boys and girls at age 6-7 years, respectively. Urban-rural height difference has continuously reduced, but weight difference has gradually widened after 3-years old which results from the excessive weight increase of urban children, 2.68 kg for rural boys aged 6-7 years but 3.26 kg for urban during the 30 years. Clear regional differences in growth are not narrowing over time. Generally, the growth level in eastern China is higher than central-western, successively higher than southern.

Conclusions: The rapid positive secular trends will still continue with the rapid socio-economic development in China. Urban-rural height difference will further narrow. Currently no sufficient evidence indicates that growth difference in inter-city has reduced. Weight increases rapidly for urban children, which does not match with height.