Secular changes in body height among children and adolescents aged 7–18 years in rural China from 1985 to 2019

This study aims to assess the secular changes in height of Chinese rural children and adolescents aged 718 years from 1985 to 2019. Height data for Chinese children and adolescents aged 718 years were obtained from the Chinese National Surveillance on Students Constitution and Health in 1985, 1995, 2005, 2014 and 2019. All provinces were divided into eastern, central, and western regions of China. T-tests were used to measure the differences in height between boys and girls by survey year. The height of rural children and adolescents aged 718 years in rural China increased progressively from 1985 to 2019. The average increase in height for boys and girls was 3.03 cm per decade and 2.37 cm per decade. There were geographical differences in the increase in height. The secular trend in height was most remarkable in the first 10 years, thereafter the increase in height slowed down, especially in the eastern region. The greatest increase in height for both boys and girls was observed in the central region, at 3.19 cm per decade and 2.54 cm per decade, respectively, during the entire period. The smallest increase in height was observed in the western region, at 2.80 cm per decade and 2.21 cm per decade during the entire period. However, the increase in height of boys and girls in the western regions (boys: 1.93 cm per decade; girls: 1.52 cm per decade) has been greater than in the central (1.47 cm and 1.31 cm per decade) and western regions (0.94 cm and 0.76 cm per decade) in the last five years. In conclusion, during the entire 34 years, the height of Chinese rural children and adolescents aged 718 years has continued to increase. More attention needs to be focused on the growth and development of children and adolescents in the western regions.