Young children with excess of weight show an impaired selenium status.

People who are overweight/obese commonly experience poorer antioxidant protection. The aim of the present study was to determine whether overweight/obesity is associated with children's selenium status. The study subjects were 573 Madrid schoolchildren aged 8 - 13 years. Their selenium intake was monitored via a three-day food record. Serum selenium concentration and blood glutathione peroxidase (GPx) activity of each subject was also determined, as was body mass index (BMI). Children with excess of weight (BMI>P85) had lower serum selenium concentrations than those of normal weight (64.6 ± 16.8 µg/L compared to 75.3 ± 12.2 µg/L; p < 0.001). Their selenium intake was also lower (1.99 ± 0.62 µg/kg compared to 2.73 ± 0.88 µg/kg; p < 0.001). A positive correlation was found between serum selenium and selenium intake (the best being obtained when intake was measured in µg/kg/day, r = 0.338, p < 0.05), while a negative relationship was seen between serum selenium and all the anthropometric variables recorded (the strongest correlation was seen between serum selenium and BMI, r = -0.390, p < 0.05). Logistic regression showed the risk of selenium deficiency (<70 µg/L) to increase with BMI [OR = 1.5031 (1.3828 - 1.6338)] and to decrease with selenium intake [OR = 0.9862 (0.9775 - 0.9949)] and age [OR = 0.6813 (0.5434 - 0.8542)] (p < 0.001). A correlation was also detected between serum selenium and GPx activity (r = 0.177; p < 0.05) but there were no significant relationships between GPx activity and any anthropometric variables, excluding the correlation with waist/hip ratio (r = -0.298; p < 0.01). Children with excess of weight have a poorer selenium status than children of normal weight, which can contribute to poor antioxidant protection. This situation could be more evident in children with central adiposity.