Trend in physical growth among Chinese urban students: Results from five national successive cross-sectional surveys within the past two decades.

OBJECTIVES

To examine the orientation, magnitude, and pace of secular trends in body height, weight, and body mass index (BMI) among Chinese urban students aged 7-18 years from 2000 to 2019.

METHODS

Data were extracted from Chinese urban students aged 7-18 years from the Chinese National Surveillance on Students' Constitution and Health in 2000, 2005, 2010, 2014, and 2019. The height, weight, and BMI of 548 419, 548 408, and 548 365 urban students aged 7-18 years, respectively, were tested. The mean differences across survey years were tested by one-way analysis of variance (ANOVA). The pace of secular trends is expressed as the change every 5 years between every two adjacent survey years.

RESULTS

Height increments between 1.9 and 6.2 cm, weight increments between 2.7 and 8.6 kg, and BMI increments between 0.9 and 1.9 kg/m were observed in boys. For girls, height increments between 1.5 and 4.9 cm, weight increments between 2.2 and 6.0 kg, and BMI increments between 0.7 and 1.7 kg/m were observed. The pace of secular trends in height decreased in the last 5 years, and the secular trends in weight and BMI have accelerated in the last 9 years compared with the previous 10 years.

CONCLUSIONS

Although the secular trend in height among Chinese urban students has slowed, it has not yet reached its genetic potential and continues to increase. The rapid increase in weight and BMI was a cause for concern. Our findings provide a basis for the future formulation of public health interventions in China.