BACKGROUND: The urban-rural disparities in overweight and obesity among children and adolescents are narrowing, and there is a need for long-term and updated data to explain this inequality, understand the underlying mechanisms, and identify priority groups for interventions. METHODS: We analyzed data from seven rounds of the Chinese National Survey on Students Constitution and Health (CNSSCH) conducted from 1985 to 2019, focusing on school-age children and adolescents aged 7-18 years. Joinpoint regression was used to identify inflection points (indicating a change in the trend) in the prevalence of overweight and obesity during the study period, stratified by urban/rural areas and sex. Annual percent change (APC), average annual percent change (AAPC), and 95% confidence interval (CI) were used to describe changes in the prevalence of overweight and obesity. Polynomial regression models were used to predict the prevalence of overweight and obesity among children and adolescents in 2025 and 2030, considering urban/rural areas, sex, and age groups. RESULTS: The prevalence of overweight and obesity in urban boys and girls showed an inflection point of 2000, with AAPC values of 10.09% (95% CI: 7.33-12.92%, t = 7.414, P <0.001) and 8.67% (95% CI: 6.10-11.30%, t = 6.809, P <0.001), respectively. The APC for urban boys decreased from 18.31% (95% CI: 4.72-33.67%, t = 5.926, P = 0.027) to 4.01% (95% CI: 1.33-6.75%, t = 6.486, P = 0.023), while the APC for urban girls decreased from 13.88% (95% CI: 1.82-27.38%, t = 4.994, P = 0.038) to 4.72% (95% CI: 1.43-8.12%, t = 6.215, P = 0.025). However, no inflection points were observed in the best-fit models for rural boys and girls during the period 1985-2019. The prevalence of overweight and obesity for both urban and rural boys is expected to converge at 35.76% by approximately 2027. A similar pattern is observed for urban and rural girls, with a prevalence of overweight and obesity reaching 20.86% in 2025. CONCLUSIONS The prevalence of overweight and obesity among Chinese children and adolescents has been steadily increasing from 1985 to 2019. A complete reversal in urban-rural prevalence is expected by 2027, with a higher prevalence of overweight and obesity in rural areas. Urgent action is needed to address health inequities and increase investments, particularly policies targeting rural children and adolescents.
Humans ; Child ; Adolescent ; Female ; Male ; Rural Population/statistics & numerical data* ; Overweight/epidemiology* ; Prevalence ; China/epidemiology* ; Pediatric Obesity/epidemiology* ; Obesity/epidemiology* ; Urban Population

OBJECTIVES: To systematically evaluate the prevalence and risk factors of non-alcoholic fatty liver disease (NAFLD) in overweight and obese children and adolescents in China. METHODS: Databases including China National Knowledge Infrastructure, Wanfang Data, VIP Database, China Biomedical Literature Database, PubMed, Embase, Web of Science, and Cochrane Library were searched, from database inception to October 2024. Two researchers independently screened the literature, extracted data, and assessed the quality of the studies according to inclusion and exclusion criteria. A Meta analysis was conducted using Stata 16.0 software. RESULTS: A total of 42 studies involving 16 481 overweight and obese children and adolescents were included. The Meta analysis results showed that the prevalence of NAFLD among overweight and obese children in China was 43% (95%CI: 37%-48%). Factors associated with NAFLD included being male (OR=1.61, 95%CI: 1.17-2.04), increased weight (MD=10.33, 95%CI: 9.08-11.57), increased waist circumference (MD=5.49, 95%CI: 3.36-7.62), longer duration of obesity (MD=0.31, 95%CI: 0.02-0.61), higher body mass index (MD=3.11, 95%CI: 2.07-4.16), elevated fasting blood glucose levels (MD=0.17, 95%CI: 0.06-0.29), higher triglyceride levels (MD=0.32, 95%CI: 0.17-0.47), elevated total cholesterol levels (MD=0.15, 95%CI: 0.10-0.21), higher low-density lipoprotein cholesterol levels (MD=0.14, 95%CI: 0.04-0.23), increased alanine aminotransferase levels (MD=24.39, 95%CI: 18.57-30.20), increased aspartate aminotransferase levels (MD=12.49, 95%CI: 9.67-15.32), elevated serum insulin levels (MD=4.47, 95%CI: 2.57-6.36), higher homeostasis model assessment-insulin resistance (MD=0.45, 95%CI: 0.30-0.59), and elevated uric acid levels (MD=55.91, 95%CI: 35.49-76.32) (P<0.05). CONCLUSIONS The prevalence of NAFLD among overweight and obese children and adolescents in China is high. Male gender, increased weight, increased waist circumference, prolonged obesity duration, higher body mass index, dyslipidemia, and elevated levels of fasting blood glucose, liver enzymes, serum insulin, homeostasis model assessment-insulin resistance, and uric acid are potential risk factors for NAFLD in this population.
Humans ; Non-alcoholic Fatty Liver Disease/etiology* ; Risk Factors ; Adolescent ; Child ; Overweight/complications* ; Prevalence ; China/epidemiology* ; Obesity/complications* ; Male ; Female

OBJECTIVES: The prevalence of overweight and obesity among children and adolescents continues to rise, becoming one of the most serious global public health issues of the 21st century. Given the differing growth and development environments between urban and rural children, associated risk factors also vary. This study aims to explore the distribution characteristics and influencing factors of overweight and obesity among urban and rural primary and secondary school students in Hunan Province, providing scientific evidence for targeted interventions. METHODS: A stratified, randomized cluster sampling method was used to select participants. A total of 197 084 students from primary and secondary schools across 14 prefectures in Hunan Province underwent physical examinations and questionnaire surveys. Population and spatial distribution characteristics of overweight and obesity were analyzed. Spatial distribution maps and spatial autocorrelation analyses were conducted using ArcGIS. Multivariate Logistic regression was used to identify influencing factors for overweight and obesity. RESULTS: The overall overweight and obesity rates among students in Hunan Province were 14.7% and 10.9%, respectively. Both rates were higher in urban areas than in rural counties (16.0% vs 13.9% for overweight; 12.1% vs 10.2% for obesity). Among both urban and rural students, boys had higher rates of overweight and obesity than girls. Higher-grade students had a higher overweight rate but a lower obesity rate than lower-grade students. In urban areas, the overweight and obesity rates of Han Chinese primary and secondary school students are lower than those of ethnic minority students (both P<0.05). In rural areas, the obesity rate of Han primary and secondary school students is lower than that of ethnic students (P<0.05). Across cities and prefectures, urban overweight and obesity rates ranged from 14.7% to 18.7% and 8.4% to 20.6% respectively, while rural rates ranged from 10.9% to 17.2% and 6.6% to 13.7% respectively. Spatial autocorrelation analysis revealed high-value clusters of overweight/obesity in urban areas of Changde and Zhangjiajie, and in rural areas of Loudi, Huaihua, and Shaoyang. Multivariate Logistic regression showed that gender, school stage, ethnicity, frequency of fresh vegetable intake, and sleep duration were associated with overweight and/or obesity in both urban and rural students. In urban students, frequency of fried food and fresh fruit intake, breakfast habits, physical activity on weekdays and holidays, and screen time on computers were also significant. In rural students, TV viewing time and sedentary duration were additional relevant factors. CONCLUSIONS The situation of overweight and obesity among primary and secondary school students in Hunan Province remains concerning. Greater attention should be paid to regions with high-value clusters of overweight/obesity, and targeted interventions should be developed based on urban-rural differences in influencing factors.
Humans ; China/epidemiology* ; Adolescent ; Male ; Female ; Rural Population/statistics & numerical data* ; Child ; Overweight/epidemiology* ; Students/statistics & numerical data* ; Urban Population/statistics & numerical data* ; Risk Factors ; Prevalence ; Obesity/epidemiology* ; Surveys and Questionnaires ; Pediatric Obesity/epidemiology* ; Schools

OBJECTIVE: This study aimed to explore the association between body mass index (BMI) and mortality based on the 10-year population-based multicenter prospective study. METHODS: A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023. Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality. Stratified analyses were performed based on the individual characteristics of the participants. RESULTS: Overall, 19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died. The underweight (< 18.5 kg/m ²) presented an increase in all-cause mortality (adjusted hazards ratio [ aHR] = 2.00, 95% confidence interval [ CI]: 1.66-2.41), while overweight (≥ 24.0 to < 28.0 kg/m ²) and obesity (≥ 28.0 kg/m ²) presented a decrease with an aHR of 0.61 (95% CI: 0.52-0.73) and 0.51 (95% CI: 0.37-0.70), respectively. Overweight ( aHR = 0.76, 95% CI: 0.67-0.86) and mild obesity ( aHR = 0.72, 95% CI: 0.59-0.87) had a positive impact on mortality in people older than 60 years. All-cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m ² ( aHR = 0.95, 95% CI: 0.92-0.98) and increased slightly above that value, indicating a U-shaped association. The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses. CONCLUSION This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years. Therefore, it is essential to consider age differences when formulating health and weight management strategies.
Humans ; Body Mass Index ; China/epidemiology* ; Male ; Female ; Middle Aged ; Prospective Studies ; Rural Population/statistics & numerical data* ; Aged ; Follow-Up Studies ; Adult ; Mortality ; Cause of Death ; Obesity/mortality* ; Overweight/mortality*

OBJECTIVE: To investigate the association between long-term exposure to ambient fine particulate matter (PM _2.5) and its constituents and the risk of incident type 2 diabetes mellitus (T2DM), and to examine the modification roles of overweight status. METHODS: This prospective study included 27,507 adults living in rural China. The annual mean residential exposure to PM _2.5 and its constituents was estimated using a satellite-based statistical model. Cox models were used to estimate the risk of T2DM associated with PM _2.5 and its constituents. Stratified analysis quantified the role of overweight status in the association between PM _2.5 constituents and T2DM. RESULTS: Over a median follow-up of 9.4 years, 3,001 new T2DM cases were identified. The hazard ratio ( HR) for a 10 μg/m ³ increase in ambient PM _2.5 was 1.30 (95% confidence interval [ CI]: 1.17, 1.45). Among the constituents, the strongest association was observed with black carbon. Being overweight significantly modified the association between certain constituents and the risk of T2DM. Participants who were overweight and exposed to the highest quartile of PM _2.5 constituents had the highest risk of T2DM ( HR: 2.46, 95% CI: 2.04, 2.97). CONCLUSIONS Our findings indicate that PM _2.5 was associated with an increased risk of T2DM, with black carbon potentially being the primary contributor. Being overweight appeared to enhance the association between PM _2.5 and T2DM. This suggests that controlling both PM _2.5 exposure and overweight status may reduce the burden of T2DM.
Humans ; Diabetes Mellitus, Type 2/chemically induced* ; China/epidemiology* ; Particulate Matter/analysis* ; Overweight/epidemiology* ; Female ; Male ; Middle Aged ; Rural Population ; Air Pollutants/analysis* ; Adult ; Prospective Studies ; Environmental Exposure/adverse effects* ; Aged ; Risk Factors

Objective: To compare the application of China growth standard for children under 7 years of age (China standards) and World Health Organization child growth standards (WHO standards) in evaluating the prevalence of malnutrition in children aged 0-<6 years in China. Methods: The research data came from the national special program for science & technology basic resources investigation of China, named "2019-2021 survey and application of China's nutrition and health system for children aged 0-18 years". Multi-stage stratified random sampling was used to recruit 28 districts (regions) in 14 provinces, autonomous regions or municipalities across the country. Children (n=38 848) were physically measured and questionnaires were conducted in the guardians of the children. The indicators of stunting, underweight, wasting, overweight and obesity were evaluated by China standards and WHO standards respectively. Chi-square test was used to comparing the prevalence of each nutritional status between the two standards, as well as the comparison between the two standards by gender and age. Results: Among the 38 848 children, 19 650 were boys (50.6%) and 19 198 were girls (49.4%), 19 480 urban children (50.1%) and 19 368 rural children (49.9%). The stunting, underweight and wasting cases in the study population were 2 090 children (5.4%), 1 354 children (3.5%) and 1 276 children (3.3%) according to the China standards, and 1 474 children (3.8%), 701 children (1.8%) and 824 children (2.1%) according to the WHO standards, respectively; the above rates according to the China standards were slightly higher than those to the WHO standards (χ²=111.59, 213.14, and 99.99, all P<0.001). The overweight and obesity cases in the study population were 2 186 children (5.6%) and 1 153 children (3.0%) according to the China standards, and 2 210 children (5.7%) and 1 186 children (3.1%) according to the WHO standards, with no statistically significant differences (χ²=0.14 and 0.48, P=0.709 and 0.488, respectively). Compared to the results based on WHO standards, the China standards showed a lower prevalence of overweight and obesity in boys (χ²=14.95 and 5.85, P<0.001 and =0.016, respectively), and higher prevalence of overweight in girls (χ²=12.60, P<0.001); but there was no statistically significant differences in girls' obesity prevalence between the two standards (χ²=2.62, P=0.106). Conclusions: In general, the prevalence of malnutrition among children aged 0-<6 years based on China standards is slightly higher than that on WHO standards. To evaluate the nutritional status of children, it is advisable to select appropriate child growth standards based on work requirements, norms or research objectives.
Male ; Female ; Child ; Humans ; Child, Preschool ; Nutritional Status ; Overweight/epidemiology* ; Thinness/epidemiology* ; Obesity/epidemiology* ; Malnutrition/epidemiology* ; Growth Disorders/epidemiology* ; China/epidemiology* ; Prevalence

From January 2019 to December 2021, overweight and obese children who visited in health outpatient Center of Hunan Children's Hospital were studied to explore and analyze the rate, related factors and patterns of multimorbidity of overweight and obesity-related diseases in children in Hunan Province. Univariate and multivariate logistic regression models were used to analyze the multimorbidity-related factors of overweight and obesity-related diseases in children. Association rules (apriori algorithm) were used to explore the multimorbidity patterns of overweight and obesity-related diseases in children. A total of 725 overweight and obese children were included in this study. The multimorbidity rate of overweight and obesity-related diseases in children was 46.07% (334/725). Age, waist circumference, the frequency of food consumption such as hamburgers and fries and adding meals before bedtime were multimorbidity-related factors of overweight and obesity-related diseases in children. The multimorbidity associated with nonalcoholic fatty liver disease (NAFLD) was relatively common. The patterns with the top three support degrees were "NAFLD+dyslipidemia","NAFLD+hypertension" and "NAFLD+hyperuricemia". The patterns with the top three confidence and elevation degrees were "Hypertension+dyslipidemia => NAFLD","Hyperuricemia => NAFLD" and "NAFLD+hypertension => dyslipidemia".
Child ; Humans ; Overweight/complications* ; Non-alcoholic Fatty Liver Disease ; Pediatric Obesity/epidemiology* ; Hyperuricemia ; Multimorbidity ; Hypertension/epidemiology* ; Dyslipidemias ; Body Mass Index ; Risk Factors

Objective: To analyze the incidence of preterm birth based on pre-pregnancy body mass index (BMI) stratification and explore the associated factors of preterm birth among pregnant women at different BMI stratifications. Methods: From February 2018 to December 2020, pregnant women who participated in China Birth Cohort Study (CBCS) and gave birth at Beijing Obstetrics and Gynecology Hospital were enrolled as the study subjects. Electronic Data Capture System and standard structured questionnaires were used to collect data related to pre-pregnancy, pregnancy, and delivery for pregnant women. Pregnant women were divided into the low-weight group, normal-weight group and overweight group based on their pre-pregnancy BMI. A Cox proportional hazards model was used to analyze the associated factors of preterm birth among pregnant women with different BMI before pregnancy. Results: A total of 27 195 singleton pregnant women were included, with a preterm birth rate of 5.08% (1 381/27 195). The preterm birth rates in the low-weight group, normal-weight group and overweight group were 4.29% (138/3 219), 4.63% (852/18 390) and 7.00% (391/5 586) respectively (P<0.001). After adjusting for relevant factors, the Cox proportional hazards model showed that the risk of preterm birth in the overweight group was 1.457 times higher than that in the normal-weight group (95%CI: 1.292-1.643). Preeclampsia-eclampsia (HR=2.701, 95%CI: 1.318-5.537) was the associated factor for preterm birth in the low-weight group. Advanced maternal age (HR=1.232, 95%CI: 1.054-1.441), history of preterm birth (HR=4.647, 95%CI: 3.314-6.515), vaginal bleeding in early pregnancy (HR=1.613, 95%CI: 1.380-1.884), and preeclampsia-eclampsia (HR=3.553, 95%CI: 2.866-4.404) were associated factors for preterm birth in the normal-weight group. Advanced maternal age (HR=1.473, 95%CI: 1.193-1.818), history of preterm birth (HR=3.209, 95%CI: 1.960-5.253), vaginal bleeding in early pregnancy (HR=1.636, 95%CI: 1.301-2.058), preeclampsia-eclampsia (HR=2.873, 95%CI:2.265-3.643), and pre-gestational diabetes mellitus (HR=1.867, 95%CI: 1.283-2.717) were associated factors for preterm birth in the overweight group. Conclusion: Pre-pregnancy overweight is an associated factor for preterm birth, and there are significant differences in the associated factors of preterm birth among pregnant women with different BMI before pregnancy.
Pregnancy ; Infant, Newborn ; Female ; Humans ; Body Mass Index ; Overweight/epidemiology* ; Premature Birth/epidemiology* ; Pre-Eclampsia/epidemiology* ; Cohort Studies ; Eclampsia ; Incidence ; Risk Factors ; Thinness/epidemiology*

Objective: To explore the obesity-related factors among primary and middle school students in Hangzhou. Methods: A stratified random cluster sampling cross-sectional study was conducted using Hangzhou city's 2016-2020 annual school health survey data. Finally, 9 213 primary and secondary school students with complete data were selected as the research objects. The standard of Overweight and Obesity Screening for School-age Children and Adolescents (WS/T 586-2018) was used to verify students' obesity. SPSS 25.0 software was applied to conduct statistical analysis on the related factors of obesity. Results: The overall obesity detection rate among primary and middle school students in Hangzhou was 8.52%. The results of logistic regression analysis showed that inadequate sleep (OR=6.507, 95%CI: 2.371-17.861, P<0.001), 3- hours (OR=5.666, 95%CI: 2.164-14.835, P<0.001) and ≥4 hours (OR=7.530, 95%CI: 2.804-20.221, P<0.001) of watching video every day in the past week, being beaten and scolded by parents in the past week (OR=1.627, 95%CI: 1.161-2.280, P=0.005), parents often reduce students' exercise time in order to let students have more time to study in the past week (OR=3.310, 95%CI: 1.243-8.819, P=0.017), age 16-18 years old (OR=0.137, 95%CI: 0.050-0.374, P<0.001), often suffering from campus violence in the past week (OR=0.332, 95%CI: 0.141-0.783, P=0.012), 1 hour of watching video every day in the past week (OR=0.023, 95%CI: 0.006-0.083, P<0.001), sometimes having breakfast (OR=0.151, 95%CI: 0.058-0.397, P<0.001) and eating breakfast every day (OR=0.020, 95%CI: 0.005-0.065, P<0.001) in the past week, eating vegetables and fruits sometimes (OR=0.015, 95%CI: 0.010-0.023, P<0.001) and every day (OR=0.020, 95%CI: 0.008-0.053, P<0.001) in the past week, eating sweet food sometimes (OR=0.089, 95%CI: 0.035-0.227, P<0.001) and every day (OR=2.568, 95%CI: 1.632-4.041, P<0.001) in the past week, eating fried food sometimes (OR=0.274, 95%CI: 0.094-0.800, P=0.018) in the past week, and having three physical education classes every week (OR=0.156, 95%CI: 0.057-0.423, P<0.001) were the main related factors affecting the occurrence of obesity in primary and secondary school students. Conclusions: With the higher obesity prevalence among primary and middle school students in Hangzhou, parents and teachers should strengthen health education for primary and middle school students, help children develop scientific eating behavior, develop positive and healthy living habits of children, and effectively prevent overweight/obesity in primary and middle school students.
Child ; Adolescent ; Humans ; Overweight/epidemiology* ; Cross-Sectional Studies ; Obesity/epidemiology* ; Feeding Behavior ; Students

Objective: To investigate the associations between the numbers of healthy lifestyles and overweight/obesity and abdominal obesity in adult twins in Shanghai. Methods: Based on the Shanghai Twin Registry System Phase Ⅱ survey data in 2017-2018, a case-control study was conducted to analyze the association between healthy lifestyles and obesity and further adjusted for confounders by a co-twin control study. Results: A total of 7 864 adult twins (3 932 pairs) were included. In the co-twin case-control analysis for monozygotic twins, compared with participants with 0 to 2 healthy lifestyles, those with 3 and 4 to 5 healthy lifestyles had a 49% (OR=0.51, 95%CI: 0.28-0.93) and 70% (OR=0.30, 95%CI: 0.13-0.69) lower risk of overweight/obesity, respectively, and a 17% (OR=0.83, 95%CI: 0.44-1.57) and 66% (OR=0.34, 95%CI: 0.14-0.80) lower risk of abdominal obesity, respectively. For each additional healthy lifestyle, the risk of developing overweight/obesity was reduced by 41% (OR=0.59, 95%CI: 0.42-0.85), and the risk of developing abdominal obesity was reduced by 37% (OR=0.63, 95%CI: 0.44-0.90). Conclusion: An increasing number of healthy lifestyles was associated with a marked decreased risk for both overweight/obesity and abdominal obesity.
Adult ; Humans ; Case-Control Studies ; China/epidemiology* ; Healthy Lifestyle ; Obesity/epidemiology* ; Obesity, Abdominal/epidemiology* ; Overweight/epidemiology* ; Twins, Monozygotic