An investigation of iodine intake and iodine nutrition status of pregnant women in different water iodine areas of Tianjin / 中华地方病学杂志

ABSTRACT

Objective:To investigate the iodine intake and iodine nutritional status of pregnant women in different water iodine areas of Tianjin, and to provide a basis for formulating appropriate intervention measures in high water iodine areas.Methods:From January to September 2016, 90, 91 and 71 pregnant women were randomly selected as research subjects in different water iodine areas in Tianjin (water iodine ≤150, > 150 - 300 and > 300 μg/L) via the random sampling method. Samples of salt, drinking water and urine were collected from pregnant women. A semi-quantitative food frequency questionnaire was used to investigate the intake of 12 kinds of food eating by pregnant women in the past year. Salt iodine content was determined by direct titration, water iodine content was determined by ceric sulfate catalytic spectrophotometry, and urinary iodine was determined by arsenic-cerium catalytic spectrophotometry.Results:There was no statistically significant difference in salt iodine intake among pregnant women in different water iodine areas ( H = 2.29, P = 0.318); the difference in drinking water iodine intake (7.50, 282.60, 544.35 μg/d) was statistically significant ( H = 223.31, P < 0.001), and further pairwise comparison found that the differences were statistically significant ( P < 0.001); the difference in food iodine intake was not statistically significant ( H = 2.19, P = 0.334). With the increase of water iodine content in various regions, the contribution rate of drinking water iodine intake gradually increased. The medians of urinary iodine in pregnant women in different water iodine areas were 113.50, 180.55 and 268.55 μg/L, respectively, and there was a positive correlation between urine iodine content and total iodine intake ( rs = 0.31, P < 0.001). Conclusions:The iodine nutrition level of pregnant women in areas with water iodine ≤150 μg/L is insufficient (< 150 μg/L), so the consumption rate of iodized salt should be increased to prevent the occurrence of iodine deficiency disorders. The iodine nutrition level of pregnant women in areas with water iodine > 300 μg/L exceeds the appropriate amount (250 - 499 μg/L), pregnant women should control the intake of foods with high iodine content and take measures to improve water as soon as possible to reduce iodine.