Shiyun Luo

Background: Childhood dyslipidemia often tracks into adulthood and contributes to early atherosclerotic changes. Although serum 25-Hydroxyvitamin D (25(OH)D) has been implicated in lipid metabolism, findings in children remain inconsistent, and whether these associations differ by overweight/obesity (ow/ob) status is unclear. We therefore aimed to investigate the associations of serum 25(OH)D concentrations and lipid profiles stratified by ow/ob status among children and adolescents aged 9–17 years. Methods: This cross-sectional study included 3067 children and adolescents from Guangzhou, southern China. Anthropometric measurements were obtained by trained staff, and ow/ob status was classified according to WHO criteria. Fasting blood samples were collected to measure serum 25(OH)D and lipid parameters. Multivariable regression analyses were adopted to determine the associations between serum 25(OH)D and lipid profiles. Stratified analysis and interaction tests were further applied according to ow/ob status. Results: Higher 25(OH)D concentrations were most consistently associated with lower TG (β = −0.026; 95% CI, −0.040 to −0.011), higher HDL-C (β = 0.025; 95% CI, 0.014 to 0.035), and lower TG/HDL-C ratios (β = −0.044; 95% CI, −0.061 to −0.027). Positive associations were also observed for TC, LDL-C, and non-HDL-C with serum 25(OH)D, but these were attenuated after further adjustment for HDL-C. No significant association was observed for the TC/HDL-C ratio. In stratified analyses, associations with several lipid parameters were observed mainly among children and adolescents without ow/ob, whereas significant inverse associations among those with ow/ob were largely limited to TG and the TG/HDL-C ratio. Significant interactions between vitamin D and ow/ob status were observed for TC and non-HDL-C, but were attenuated after further adjustment for HDL-C. Conclusions: In this cross-sectional study, serum 25(OH)D was associated with several lipid parameters among children and adolescents, most consistently with TG, HDL-C, and the TG/HDL-C ratios. Stratified analyses showed different vitamin D–lipid association patterns across ow/ob status, with statistically significant interactions observed only for TC and non-HDL-C. The attenuation of several associations after adjustment for HDL-C suggests that HDL-C may be involved in these observed patterns. Future longitudinal studies are needed to examine causality of vitamin D–lipid associations and the potential role of HDL-C in these associations.

Background: Iron deficiency (ID) progresses through three stages: iron deficiency stores (IDS), iron deficiency erythropoiesis (IDE), and iron deficiency anemia (IDA). Neglecting subclinical ID may be harmful to school-aged children and increase the public health burden. Although diet is a key modifiable factor, most studies only focus on overall ID or merely the clinical IDA stage. This study combines a dietary index with pattern analysis to take advantage of their complementary strengths and explore their associations with ID progression. Methods: This cross-sectional study included 2493 participants from rural Guangzhou between June 2022 and May 2023. Demographic, lifestyle, anthropometric, and dietary data were collected via structured questionnaires. Blood samples were analyzed for iron status. Factor analysis identified dietary patterns, and the Chinese Dietary Guidelines Index for Children and Adolescents [CDGI(2021)-C] assessed dietary quality. We used ordinal logistic regression, multivariable logistic regression, and restricted cubic spline (RCS) models to examine dietary associations with ID stages. Results: IDS, IDE, and IDA proportions were 68.22%, 17.45%, and 14.33%, respectively. All four dietary patterns correlated positively with CDGI(2021)-C, most strongly for the fruit–vegetable (r_s = 0.552) and cereal–tuber–legume patterns (r_s = 0.386). Higher CDGI(2021)-C (OR = 0.852, 95% CI: 0.751–0.966, p-trend = 0.012), fruit–vegetable (OR = 0.866, 95%CI: 0.748–0.993, p-trend = 0.047), and meat–offal patterns (OR = 0.733, 95%CI: 0.611–0.868, p-trend < 0.001) were inversely associated with advancing ID stages, while the snack–fast food pattern was positively associated (OR = 1.233, 95% CI: 1.094–1.381, p-trend < 0.001). In IDS, higher adherence to CDGI(2021)-C, fruit–vegetable, and meat–offal patterns was associated with lower odds (all p-trend < 0.05). RCS showed nonlinear associations for the snack–fast food and cereal–tuber–legume patterns, with risk peaking at moderate-to-high adherence to these patterns (both p-nonlinear < 0.05). In IDE and IDA, the snack–fast food pattern risk rose steeply at moderate-to-high adherence (p-nonlinear = 0.036), whereas the cereal–tuber–legume pattern’s ORs fluctuated near 1 (p-nonlinear = 0.020). Conclusions: Dietary pattern and index analyses showed consistent associations across ID stages. Adherence to dietary guidelines slows ID progression, especially in early subclinical stages. More fruits, vegetables, and heme-iron-rich foods, alongside less fast food and snacks, slow ID progression. Though dietary intervention effects weaken in later stages, reducing fast food and snacks confers long-term benefits. These findings inform targeted nutrition policies to prevent ID progression in children.

Background: Childhood metabolic syndrome (MetS) represents a growing public health concern in China, with diet emerging as a critical modifiable risk factor. Although numerous studies have explored the relationship between dietary patterns and MetS, the specific influence of dietary patterns associated with serum uric acid (SUA) levels in the young population remains poorly understood. The purpose of this study is to investigate the relationship between an SUA-related dietary pattern and MetS risk among children aged 9–17 years in Guangzhou, China. Methods: A cross-sectional study was conducted in Guangzhou from March 2023 to May 2024, including 4181 participants. To identify the dietary pattern associated with SUA, we employed reduced-rank regression (RRR) using 15 predefined food groups. The multivariate logistic regression models were applied to evaluate the association between the SUA-related dietary pattern scores (as continuous variables and tertiles) and the risk of MetS and its five components. Results: The SUA-related dietary pattern was characterized by high consumption of meat & meat products and beverages, and low consumption of fresh vegetables, fresh fruits & their products, eggs, dairy products, and sugary food. After adjusting for confounding factors, each one-unit increase in the SUA-related dietary pattern score corresponded to 27% higher odds of MetS (OR = 1.27, 95% CI: 1.00–1.62), and 24% higher odds of central obesity (OR = 1.24, 95% CI: 1.11–1.38). In subgroup analyses, higher adherence to the SUA-related dietary pattern scores was linked to significantly increased odds of MetS (adjusted OR = 1.69, 95% CI: 1.18–2.42) and central obesity (adjusted OR = 1.39, 95% CI: 1.20–1.62) among participants with insufficient physical activity. Conclusions: Higher adherence to the SUA-related dietary pattern was associated with higher odds of MetS in Chinese children, particularly among those with insufficient physical activity. The results provide new insights into the relationship between dietary patterns and childhood MetS, offering dietary strategies focused on managing SUA levels to prevent MetS.

Background: Elevated serum uric acid (SUA) levels in young people have become a significant public health concern. Dietary habits are a key factor influencing SUA levels. This study aimed to investigate dietary patterns (DPs) of children and adolescents and their associations with SUA. Methods: This cross-sectional study included children and adolescents in Guangzhou, China. We used structured questionnaires to collect data on demographics, lifestyle, and dietary intake, and we collected blood samples for biochemical analysis. DPs were identified by factor analysis. We used robust linear regression to examine the association between these patterns and SUA levels. Parallel mediation analysis was utilized to assess the mediating role of body mass index (BMI) Z-score and waist circumference (WC). Results: The study encompassed 4100 children and adolescents between ages 9–17. The median SUA level was 374 (IQR: 319, 438) μmol/L and the prevalence of hyperuricemia was 41.7%. We identified four DPs, including plant-based, snack–beverage, highprotein, and meat–carbohydrate patterns. There was a positive correlation between the meat–carbohydrate pattern and SUA (β = 3.67 μmol/L, 95% CI: 1.22–6.12). The Q4 group of the highprotein pattern was associated with higher SUA levels (9.17 μmol/L, 95% CI: 2.41–15.93) compared to the Q1 group. BMI Z-score and WC mediated the association between the meat–carbohydrate pattern and SUA. Conclusions: Our findings suggest that BMI Z-score and WC mediated the association between the meat–carbohydrate pattern and SUA. This study emphasizes the significance of targeted dietary interventions for weight control in addressing the increasing SUA levels in children and adolescents. Future research could focus on exploring the molecular mechanisms, developing personalized dietary intervention programs, and conducting multicenter prospective cohort studies.

Background: Childhood obesity is a major public health challenge in the 21st century, and diet is one of the key modifiable factors in its prevention. This study examined the link between dietary patterns of children and general and central obesity, including the role of C-reactive protein (CRP). Methods: This study enrolled 2413 children aged 9–17. Anthropometric measurements, CRP levels, and dietary data were collected. Factor analysis identified dietary patterns, and logistic regression examined the association between CRP levels and childhood obesity. Multiple linear regression determined the correlation between dietary patterns and CRP. Mediation analysis assessed the role of CRP in the link between dietary patterns and childhood obesity. Results: Three dietary patterns were identified. The rice and meat pattern was significantly correlated to the risk of childhood obesity (OR = 1.166, 95%CI: 1.000, 1.359 for general obesity; OR = 1.215, 95%CI: 1.071, 1.377 for central obesity). CRP was positively correlated with childhood obesity risk (OR = 2.301, 95%CI: 1.776, 2.982 for general obesity; OR = 2.165, 95%CI: 1.738, 2.697 for central obesity). The fruit and vegetable pattern was inversely related to CRP (β= −0.059, 95%CI: −0.081, −0.036), while the snack pattern was positively correlated (β= 0.043, 95%CI: 0.020, 0.065). CRP had a suppressive effect on the association between the fruit and vegetable pattern and snack pattern with childhood obesity. Conclusions: This study revealed the rice and meat pattern as a risk factor for childhood obesity, and cross-sectional evidence linked the fruit and vegetable pattern and snack pattern to childhood obesity risk, mediated by CRP.

Globally, the high consumption levels of sugar-sweetened beverages (SSBs) and their effect on health have drawn significant attention. This study aimed to identify the consumption patterns of SSBs among children in rural areas of Guangzhou, China, and explore their association with undernutrition. A total of 1864 children aged 9–17 years old were included in this study. Demographics, lifestyle behaviors, and anthropometric and dietary information were collected. Factor analysis was used to identify patterns of SSBs, while nutritional status was assessed using Body Mass Index (BMI). Latent class analysis was used to establish dietary preference models. Log-binomial regression analysis was used to analyze the association between SSBs consumption patterns and undernutrition. The undernutrition prevalence in children was 14.54–19.94% in boys and 9.07% in girls. Three SSB consumption patterns were identified, including the plant protein pattern, dairy-containing pattern, and coffee pattern. Both medium-high (Q3) and the highest (Q4) scores in the dairy-containing pattern were positively associated with the risk of undernutrition, especially in boys. Furthermore, the highest scores in the plant protein pattern and coffee pattern were positively associated with the risk of undernutrition in children aged 9–10 years old. The dairy-containing pattern was a risk factor for undernutrition in children, especially for boys; the plant protein patterns and coffee patterns were risk factors for undernutrition in children aged 9–10 years old. The findings of the study can provide scientific evidence and policy recommendations for improving children’s health conditions.