[Secular trend in overweight and obesity among Chinese children and adolescents of 7-18 years old during 2000-2019].

Objective: To understand the current situation and trend of overweight and obesity among Chinese children and adolescents aged 7-18 years from 2000 to 2019.

Methods: The body mass index(BMI) data of 1 100 303 Han children and adolescents aged 7-18 years by national students fitness and health survey report in 2000, 2005, 2010, 2014 and 2019 were selected. The "1985 height standard weight method" was used to screen overweight and obesity, and the detection rate, growth rang and growth rate of overweight and obesity were calculated by sex and age. Statistical analysis was performed by t-test, general linear regression, chi square test, chi square trend test.

Results: From 2000 to 2019, BMI of Chinese children and adolescents aged 7-18 years showed an increasing trend(all P-trend< 0.001). The overweight rate of boys and girls increased from 9.42% and 7.23% in 2000 to 15.44% and 13.34% in 2019(χ~(2 )linear trend = 2531.626 and 2955.485, all P<0.001). The obesity rate increased from 6.57% and 3.43% in 2000 to 18.41% and 10.23% in 2019(χ~2 linear trend = 9101.419 and 5300.488, all P<0.001). The obesity rate of boys and girls at different ages in each year was statistically significant(all P<0.001). From 2000 to 2014, the growth rate of overweight rate of boys and girls continued to increase, reaching the maximum growth rate of 0.52%/year and 0.50%/year from 2010 to 2014, and then dropped to 0.09%/year and 0.29%/year in 2019. From 2014 to 2019, the growth rate of obesity of boys and girls(0.70%/year for boys and 0.51%/year for girls) was slightly lower than the maximum value from 2010 to 2014(0.92%/year for boys and 0.58%/year for girls), but still higher than that before 2010. From the perspective of age, the growth rate of overweight rate of boys and girls in the low age group decreased significantly, but the growth rate of obesity rate in the high age group increased significantly, and obesity showed a trend of changing from low age to old age.

Conclusion: The detection rate of overweight and obesity among Chinese children and adolescents continued to increase from 2000 to 2019, and the growth rate from 2014 to 2019 was less than the maximum value reached in 2010 to 2014. From 2014 to 2019, the overweight of boys and girls in the low age group was effectively suppressed, and the obesity rate of boys and girls in the high age group accelerated, it is not optimistic.