Association of whole blood copper, magnesium and zinc levels with metabolic syndrome components in 6–12-year-old rural Chinese children: 2010–2012 China National Nutrition and Health Survey
Abstract Background: Copper (Cu), magnesium (Mg) and zinc (Zn) are essential elements that participate in a series of oxidative stress and inflammation pathways related to metabolic reactions. Many studies have analyzed the relationship between Cu, Mg and Zn and metabolic syndrome (MetS) in adolescents and adults, but there have been few studies of children. We aimed to investigate the association of whole blood Cu, Mg and Zn with MetS components in 6–12-year-old rural Chinese children. Methods: A total of 911 children (51.2% male, 48.7% female) aged 6–12 years were enrolled from the 2010–2012 China National Nutrition and Health Survey. Basic characteristics, metals and MetS component parameters were collected. Multivariate logistic regression analysis was performed to examine the independent relationship between metals and the incidence of MetS components.Results: Copper was positively associated with elevated waist circumference when analyzed alone (OR=2.00, 1.18–3.28). Combined with Zn, this association approached zero. For elevated triglyceride levels, the combination of low Cu and high Zn showed the opposite association with triglyceride relative to Cu alone (OR=2.21, 1.18–4.13 versus OR=0.33, 0.16–0.65, respectively), but was similar to the analysis of Zn alone (OR=2.12, 1.10–4.10). There was no association between whole blood Mg and waist circumference. However, the presence of both high Cu and high Mg levels significantly increased the risk of waist circumference exceeding the standard value (OR=2.03, 1.26–3.27). In addition, separate analysis of the distribution of Mg and Zn found no association with the risk of reduced high density lipoprotein-cholesterol (HDL-C); but high Zn combined with low Mg negatively associated with the risk of reduced HDL-C levels (OR=0.47, 0.28–0.77). Conclusions: Both the single and combined effects of Cu, Mg and Zn were associated with components of MetS. These results indicate the importance of combined analysis of multiple elements, and also provide new avenues for the early screening of MetS. The current results need to be further investigated in future work and other populations.