Association of whole blood copper, zinc and magnesium levels with risk of metabolic syndrome components in Chinese rural 6-12 years old children: the 2010-2012 China National Nutrition and Health Survey

Abstract Background Copper, zinc and magnesium are essential elements and participate in a series of oxidative stress and inflammation related to metabolic reactions. There are many studies analyzed the relationship between Cu, Zn, Mg and metabolic syndrome(MetS), which involved in adults and adolescents, but there are still few in children. Objective We aim to estimate the association of whole blood copper, zinc and magnesium with metabolic syndrome components in Chinese rural 6–12 years old children. Method: A total of 911 children aged 6–12 were enrolled from the 2010–2012 China National Nutrition and Health Survey in this study. The basic characteristics, metals and MetS components parameters were collected. Multivariate logistic regression analysis was performed to confirm the independent relationship between metals and the incident of MetS components. Results Elevated waist was positively associated with higher whole blood Cu concentration(OR = 2.00) and higher ratio of Cu/Zn(OR = 2.08), whereas elevated TG was negatively associated with higher Cu (OR = 0.33) and higher Cu/Zn(OR = 0.35) level. And higher level of Zn (OR = 2.12) and Mg (OR = 2.34) were both positively associated with elevated TG. In the combination of low Cu and high Zn level, it increased the risk of elevated TG(OR = 2.21), which consistent with the single analysis of these two metals. Mg has no significant effect on elevated waist when analysis alone. However, when there was high Mg and Cu at the same time, the risk of elevated waist increased significantly (OR = 2.03). In addition, different from single analysis of Zn and Mg, when high Zn and low Mg combined, it can significantly decreased the risk of reduced HDL-C (OR = 0.47). Conclusion The level of whole blood Cu, Zn, Cu/Zn and Mg within the normal range in children is associated with the risk of MetS components, especially in elevated TG and elevated waist. And the combination of each two metals has also shown to be correlated to MetS components. The future research will conduct a cohort to further confirm these findings. And the results will also need to be verified in other populations.