Association of whole blood copper, zinc, calcium, magnesium, and iron with non-alcoholic fatty liver disease in overweight and obese children.

Objectives: Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disorder in overweight and obese children, and its etiology and pathogenesis remain unclear, lacking effective preventive and therapeutic measures. This study aims to explore the association between whole blood copper, zinc, calcium, magnesium and iron levels and NAFLD in overweight and obese children aged 6 to 17 years, providing a scientific basis for the prevention and intervention of early NAFLD in overweight and obese children.

Methods: A cross-sectional study design was used to collect relevant data from overweight and obese children who visited the Hunan Children's Hospital from January 2019 to December 2021 through questionnaire surveys. Fasting blood samples were collected from the subjects, and various indicators such as blood glucose, blood lipid, and mineral elements were detected. All children were divided into an overweight group (=400) and a NAFLD group (=202). The NAFLD group was divided into 2 subgroups according to the ALT level: A non-alcoholic fatty liver (NAFL) group and a non-alcoholic steatohepatitis (NASH) group. Logistic regression analysis was used to analyze the association between minerals (copper, zinc, calcium, magnesium, and iron) and NAFLD, NAFL and NASH.

Results: A total of 602 subjects were included, of whom 73.6% were male, with a median age of 10 (9, 11) years, and a body mass index (BMI) of 24.9 (22.7, 27.4) kg/m. The intergroup comparison results showed that compared with the overweight group, the NAFLD group had higher levels of age, BMI, diastolic blood pressure (DBP), systolic blood pressure (SBP), triglyceride (TG), low density lipoprotein (LDL), alanine transaminase (ALT) and aspartate aminotransferase (AST), and lower level of high density lipoprotein (HDL). The NAFL group had higher levels of age, BMI, DBP, SBP, ALT, and AST, and lower levels of HDL compared with the overweight group. The levels of age, BMI, DBP, SBP, TG, LDL, ALT, and AST of NASH were higher than those in the overweight group, while the level of HDL was lower than that in overweight group (all <0.017). After adjusting for a variety of confounders, the OR of NAFLD for the highest quantile of iron was 1.79 (95% 1.07 to 3.00) compared to the lowest quantile, and no significant association was observed between copper, zinc, calcium, and magnesium, and NAFLD. The subgroup analysis of NAFLD showed that the OR for the highest quantile of iron in children with NAFL was 2.21 (95% 1.26 to 3.88), while no significant association was observed between iron level and NASH. In addition, no significant associations were observed between copper, zinc, calcium, and magnesium levels and NAFL or NASH.

Conclusions: High iron level increases the risk of NAFLD (more likely NAFL) in overweight and obese children, while copper, zinc, calcium, magnesium, and other elements are not associated with the risk of NAFLD in overweight and obese children.