The Chinese Adolescent Cohort Study: Design, Implementation, and Major Findings

Association of sociodemographic and lifestyle factors and dietary intake with overweight and obesity among U.S. children: findings from NHANES

Childhood overweight/obesity is a serious problem that has not been adequately addressed. As a key factor affecting weight gain, the association between dietary intake with childhood overweight and obesity is still unclear. The objective of this study was to analyze the association between sociodemographic, lifestyle factors and dietary intake with overweight or obesity. We used data from a large cross-sectional National Health and Nutrition Examination Survey (NHANES). The U.S. children aged 6-15 years with both weight data and dietary data were included. For univariate analysis of sociodemographic data, t tests was performed for continuous variables and chi-square tests was performed for discrete variables. Dietary intakes were described by median and quartile, and differences in dietary intake between children with normal weight and children with overweight or obesity were compared by rank sum tests. A modern statistical shrinkage technique, LASSO regression was used to examine the association between dietary intake and childhood obesity. Our study confirms that Hispanic ethnicity, increasing age, passive exposure to smoking, higher protein intake, and higher caffeine intake were positively associated with child overweight or obesity. Additionally, non-Hispanic White race, higher physical activity levels, higher household income, and higher vitamin A intake were negatively associated with child overweight or obesity.

Age-Dependent and Body Composition-Dependent Association of Child Gut Microbial Enterotype With Puberty Timing: A Chinese Cohort

CONTEXT

Puberty timing, which is vital for adult well-being, has recently been suggested to be linked to specific gut taxa. However, the impact of comprehensive gut microbiome structure assessed by enterotype on puberty timing remains unknown.

OBJECTIVE

Investigate the prospective association of gut microbial enterotype with puberty timing and the potential interaction of age and body composition.

METHODS

This study included 1826 children from the Chinese Adolescent Cohort Study, a cohort that has collected information on sociodemographics, dietary intake, physical activity, anthropometry, and pubertal development of children aged 6-8 years since 2013 and follows them up annually until the age of 15 years. Fecal samples have been collected annually since 2019 and analyzed for 16S rRNA sequencing and targeted fecal metabolomics. Cox proportional hazard regression models were used to investigate the prospective association of enterotype with puberty timing and the impact of age and body mass index (BMI) sex- and age-independent standard deviation score (SDS).

RESULTS

592 (32.4%) and 1234 (67.6%) children belonged to the Prevotella-rich enterotype and the Bacteroides-rich enterotype, respectively. Children with the Bacteroides-rich enterotype experienced their menarche/voice break later than those with the Prevotella enterotype (hazard ratio 0.53, 95% CI 0.28-0.98), P = .02). Moreover, this association was more pronounced among younger children with higher BMI SDS (P for interaction = .006).

CONCLUSION

Our findings supported a role for gut microbial communities in pubertal development, in which younger children with higher body mass seems more sensitive.

Correlation between lifestyle patterns and overweight and obesity among Chinese adolescents

Lifestyles such as physical exercise, sedentary behavior, eating habits, and sleep duration are all associated with adolescent overweight and obesity. The purpose of this study was to investigate how Chinese adolescents' lifestyles clustered into different lifestyle patterns, and to analyze the correlation between these patterns and adolescent overweight and obesity. The investigated respondents included 13,670 adolescents aged 13-18 from various administrative regions in China. Latent class analysis was employed to cluster the lifestyles of adolescents, χ2 test and Logistic regression were used to explore the relationship between lifestyle patterns and overweight and obesity in adolescents. The results identified 6 types of Chinese adolescents' lifestyle patterns, as well as the significant differences in gender and age. The adolescents with high exercise-high calorie diet had the lowest risk of overweight and obesity, and the adolescents with low consciousness-low physical activity and low consciousness-unhealthy had the highest risk of overweight and obesity, which were 1.432 times and 1.346 times higher than those with high exercise-high calorie diet, respectively. The studied demonstrated that there was a coexistence of healthy behaviors and health-risk behaviors in the lifestyle clustering of Chinese adolescents. Low physical exercise and high intake of snacks and carbonated beverages were the most common. Physical exercise and health consciousness were the protective factors of overweight and obesity in adolescents.

Prospective association of dietary soy and fibre intake with puberty timing: a cohort study among Chinese children

BACKGROUND

Dietary phytoestrogens have been suggested to influence puberty timing, a critical stage for well-being in adulthood. We hypothesized that childhood soy intake might prospectively influence puberty timing and that dietary fibre and the key isoflavone metabolite equol might play roles.

METHODS

Cox proportional hazard regression models were performed in 4781 children (2152 girls and 2629 boys) aged 6-8 years old from the Chinese Adolescent Cohort Study for whom a food frequency questionnaire at baseline and information about potential confounders were available. Anthropometry and pubertal status including age at Tanner stage 2 for breast development (B2) or age at the initiation of gonadal growth (G2), and age at menarche (M) or voice break (VB) were assessed annually. Equol excretion was determined by urine samples from 1311 participants.

RESULTS

Among girls and boys, higher soy intake was associated with later puberty timing (hazard ratio (HR)-B2: 0.88 (95% CI, 0.80-0.96), p=0.02; HR-M, 0.87 (0.77-0.94), p=0.01; HR-G2, 0.91 (0.82-0.98), p=0.013; HR-VB, 0.90 (0.82-0.9), p=0.02), independent of prepubertal body fatness and fibre intake. These associations were more pronounced among children with a high urinary equol level (p_{for-interaction} ≤ 0.04) or with a high cereal fibre intake (p_{for-interaction} ≤ 0.06). Intake of dietary fibre or its subtype was not prospectively associated with puberty onset after adjusting for dietary soy intake (p≥0.06).

CONCLUSION

Higher childhood soy intake is prospectively associated with later puberty timing in both Chinese girls and boys, independent of prepubertal body fatness, and the association is particularly pronounced among individuals with a higher urinary equol level.

Dual Burden of Malnutrition Among Adolescents With Hunger Aged 12-15 Years in 41 Countries: Findings From the Global School-Based Student Health Survey

Background: Hunger is a pandemic among adolescents, resulting in both underweight and obesity, and posing a substantial health challenge.

Objective: To estimate the dual burden of malnutrition among adolescents with hunger.

Design: Data were from the Global school-based Student Health Survey (GSHS). In total, data from 26,986 adolescents with hunger across 5 regions and 41 countries between 2010 and 2015 were analyzed in this study. Weighted prevalence and mean estimates of underweight, overweight, and obesity were calculated by gender, age, and country. Prevalence and 95% confidence intervals (CI) were calculated for regional and country-level income.

Results: The total prevalence of underweight, overweight and obesity among young adolescents with hunger was 6.2% (95% CI: 4.4–8.0%), 25.1% (95% CI: 20.3–29.9%) and 8.9% (95% CI: 6.5–11.3%), respectively. Southeast Asia had the highest prevalence of underweight (17.2%; 95% CI: 7.3–27.0%). America had the highest regional prevalence of obesity (11.1%; 95% CI: 7.2–15.1%) and overweight (28.9%; 95% CI: 21.9–35.9%). Low income countries had relatively high prevalence of underweight (11.5%; 95% CI: 3.2–19.9%). High income countries had the highest prevalence of obesity (17.4%; 95% CI: 14.9–19.9%) and overweight (38.7%; 95% CI: 32.0–45.4%). The co-existence of underweight and overweight among adolescents with hunger was highest in the Eastern Mediterranean region, and in upper-middle and high-income countries.

Conclusions: There is a dual burden of underweight and obesity among adolescents with hunger aged 12–15 years, which differs between geographical regions. The integration of targeted interventions and policies is required to simultaneously address both underweight and increasing rates of obesity among adolescents with hunger in different regions.