Effects of iodine excess on antioxidant capacity and blood lipid level in adult / 中华地方病学杂志

ABSTRACT

Objective:To study the effect of iodine excess on antioxidant capacity and blood lipid in adult.Methods:A survey was conducted in areas with different iodine nutrition levels in Shandong and Shanxi provinces to collect fasting morning urine and venous blood samples of adults. Urinary iodine, serum levels of superoxide dismutase(SOD), malondialdehyde (MDA), total cholesterol (TCHO), triglyceride (TG), apolipoprotein A1 (apoA1) and apolipoprotein B (apoB), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were determined. According to the median urinary iodine of the population in the investigated village, they were divided into appropriate iodine group (100-299 μg/L) and iodine excess group (≥300 μg/L) . Multiple linear regression was used to analyze the effects of iodine nutrition and other factors on oxidative stress indexes and blood lipids. Partial correlation analysis was used to analyze the relationship between iodine nutrition and oxidative stress indexes and blood lipids.Results:A total of 1 049 subjects were included, including 471 in the appropriate iodine group and 578 in the iodine excess group. The median (quartile) urinary iodine of the appropriate iodine group and the iodine excess group was 228.70 (157.02, 341.49) and 558.73 (298.06, 985.06) μg/L, respectively. The serum SOD level of the appropriate iodine group and the iodine excess group was 12.60 (10.83, 14.10) and 11.29 (9.18, 13.10) U/ml, respectively, and the difference between the groups was statistically significant ( U = 92 697.50, P < 0.001). There were statistically significant differences in serum TG, HDL-C and apoB levels between the appropriate iodine group and the iodine excess group ( U = 108 879.50, 96 613.50, 99 050.50, P < 0.05). The results of multiple linear regression showed that after excluding age, gender and body mass index (BMI), there was a negative correlation between iodine nutrition and serum SOD and HDL-C levels [standard regression coefficient ( β) = - 0.196, - 0.294, P < 0.001]. Partial correlation analysis showed that there was a negative correlation between iodine nutrition and serum SOD and HDL-C levels [correlation coefficient ( r) = - 0.16, - 0.09, P < 0.05]. Conclusion:Excessive iodine intake affects oxidative stress and lipid metabolism in human body.