Since the reform and opening up in China, socio-economic development has developed rapidly, and the basic indicators such as children's height and body mass have risen rapidly. Previous studies have shown that the growth in height of Chinese children has slowed in recent years, while the growth in body mass has accelerated, leading to a high prevalence of overweight and obesity currently. Investigating the current growth and nutritional status of Chinese children is important to prevent and address the negative effects of growth trends.

To analyse the trends of growth and overweight/obesity in Chinese children aged 7 to 12 years from 2014 to 2020, and provide a scientific basis for formulating measures to promote children's physical fitness and prevent obesity.

In this study, height, body mass and BMI data of 10 817 children aged 7 to 12 years from four surveys of the China Family Panel Studies (CFPS) in 2014, 2016, 2018 and 2020 were selected in May 2022. The trends of height, body mass, prevalence of overweight, obesity and overweight/obesity stratified by gender and urban/rural areas. Logistic regression analysis was also used to explore the factors influencing overweight and obesity among children aged 7 to 12 years in China from 2014 to 2020.

Compared with 2014, the height of 7 to 12 years urban female children, rural male children and rural female children in 2020 increased by 3.8 cm (95%CI=1.3-6.2 cm), 6.5 cm (95%CI=4.3-8.5 cm), 6.6 cm (95%CI=4.3-8.8 cm) respectively Compared with 2014, the body mass of 7 to 12 years urban male children, urban female children, rural male children and rural female children in 2020 increased by 2.3 kg (95%CI=0.8-3.9 kg), 2.1 kg (95%CI=0.6-3.7 kg), 3.0 kg (95%CI=1.7-4.2 kg), 3.0 kg (95%CI=1.8-4.2 kg), respectively, the difference was statistically significant (P<0.05). The prevalence of overweight/obesity among boys increased from 26.5% to 29.5%, the prevalence of obesity and overweight/obesity among girls decreased from 12.1% and 21.1% to 7.9% and 17.3%, the prevalence of overweight and overweight/obesity among urban children increased from 11.7% and 21.6% to 14.9% and 26.4%, and the prevalence of obesity and overweight/obesity among rural children decreased from 14.3% and 25.8% to 11.2% and 21.6% from 2014 to 2020, respectively, which were statistically significant (P<0.05). The results of multivariate Logistic regression analysis showed that age and sex were the influencing factors for prevalence of overweight in children (P<0.05) ; urban/rural areas, age, and gender were the influencing factors for prevalence of obesity and overweight in children (P<0.05) ; age was the influencing factor for prevalence of obesity in boys (P<0.05) ; age and year were the influencing factors for prevalence of obesity in boys (P<0.05) ; age was the influencing factor for prevalence of overweight in girls (P<0.05) ; urban/rural areas, age and year were the influencing factors for prevalence of overweight and obesity in girls (P<0.05) .

From 2014 to 2020, the body shape of children aged 7 to 12 years in China increased rapidly, with greater increase in rural areas than urban areas, and the gap between urban and rural areas has been narrowing. Meanwhile, the prevalence of overweight and obesity in boys and urban children continued to increase, while that in girls and rural children decreased. Rural/urban areas, age and gender are factors influencing the prevalence of overweight/obesity in children.

自改革开放以来，中国的社会经济快速发展，儿童的身高、体质量等基础指标快速上升。既往研究显示中国儿童的身高增长放缓，体质量的增长加速，导致了超重和肥胖的高患病率，调查当前中国儿童的生长发育与营养状况对于预防及应对生长趋势的消极影响十分重要。

分析2014—2020年中国7~12岁儿童生长趋势和超重肥胖趋势，为制定儿童体质促进和肥胖预防措施提供科学依据。

本研究于2022年5月选取中国家庭追踪调查（CFPS）2014年、2016年、2018年和2020年4次调查中10 817名7~12岁儿童的身高、体质量和BMI数据，以性别和城乡分层，比较2014—2020年不同性别和城乡间身高、体质量、超重患病率、肥胖患病率和超重肥胖患病率的流行趋势，并采用Logistic回归分析探讨中国2014—2020年7~12岁儿童超重肥胖影响因素。

2020年7~12岁城市女性儿童、乡村男性儿童、乡村女性儿童的身高相较于2014年增高了3.8 cm（95%CI=1.3~6.2 cm）、6.5 cm（95%CI=4.3~8.5 cm）、6.6 cm（95%CI=4.3~8.8 cm）；2020年7~12岁城市男性儿童、城市女性儿童、乡村男性儿童、乡村女性儿童的体质量相较于2014年增高了2.3 kg（95%CI=0.8~3.9 kg）、2.1 kg（95%CI=0.6~3.7 kg）、3.0 kg（95%CI=1.7~4.2 kg）、3.0 kg（95%CI=1.8~4.2 kg），差异有统计学意义（P<0.05）。2014—2020年间，男性儿童的超重肥胖率从26.5%上升至29.5%，女性儿童的肥胖率和超重肥胖率分别从12.1%和21.1%下降至7.9%和17.3%，城市儿童的超重率和超重肥胖率分别从11.7%和21.6%上升至14.9%和26.4%，乡村儿童的肥胖率和超重肥胖率分别从14.3%和25.8%下降至11.2%和21.6%，差异均有统计学意义（P<0.05）。多因素Logistic回归分析结果显示，年龄和性别是儿童超重的影响因素（P<0.05）；城乡、年龄和性别是儿童肥胖和超重肥胖的影响因素（P<0.05）；年龄是男性儿童肥胖的影响因素（P<0.05）；年龄和年份是男性儿童超重肥胖的影响因素（P<0.05）；年龄是女性儿童超重的影响因素（P<0.05）；城乡、年龄和年份是女性儿童肥胖和超重肥胖的影响因素（P<0.05）。

2014—2020年间，中国7~12岁儿童身体形态快速增长，乡村增量大于城市，城乡差距缩小，同时男性和城市儿童超重肥胖患病率继续增加，女性和乡村儿童下降。城乡、年龄和性别是儿童超重肥胖患病率的影响因素。