A comparative study on iodine nutritional status of the populations consuming iodized salt and non-iodized salt in iodine adequate areas
10.3760/cma.j.cn231583-20220906-00309
- VernacularTitle:适碘地区供应碘盐和供应未加碘盐的人群碘营养现状调查
- Author:
Jin YANG
1
;
Yanli TENG
;
Jingya HENG
;
Gaili WANG
;
Xiaofeng LI
Author Information
1. 河南省疾病预防控制中心地方病预防控制所，郑州 450016
- Keywords:
Iodine;
Urine;
Salts;
Thyroid
- From:
Chinese Journal of Endemiology
2024;43(6):477-481
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To compare iodine nutritional status of different populations consuming iodized salt and non-iodized salt in iodine adequate areas, and to provide a basis for formulating iodine supplementation strategies.Methods:In October 2021, Luyi County in Henan Province was selected as an iodine adequate area consuming iodized salt, while Ningling County was selected as an iodine adequate area consuming non-iodized salt. Stratified by water iodine (50 - 59, 60 - 69, 70 - 79, 80 - 89, 90 - 100 μg/L), one village was selected from each layer. One hundred children aged 8 - 10, one hundred adults, and 20 pregnant women were selected from each village to collect their urine and salt samples for testing salt and urinary iodine, and their thyroid gland was measured by ultrasound.Results:A total of 600 salt samples in Luyi County were collected, with the coverage rate of iodized salt (99.8%, 599/600) and the consuming rate of qualified iodized salt (95.5%, 573/600). A total of 1 008 salt samples in Ningling County were collected, with the rate of non-iodized salt (93.8%, 946/1 008). The median urinary iodine of children in Luyi County ( n = 240) was higher than that in Ningling County ( n = 468, 305.0 vs 232.0 μg/L, Z = - 8.10, P < 0.001). There was no statistically significant difference in median urinary iodine between pregnant women in Luyi County ( n = 120) and Ningling County ( n = 53, 240.0 vs 236.0 μg/L, Z = - 1.02, P = 0.306). The median urinary iodine of adults in Luyi County ( n = 238) was higher than that in Ningling County ( n = 486, 289.0 vs 178.5 μg/L, Z = - 11.14, P < 0.001). Children's urinary iodine ( r s = 0.21, P = 0.001) in Luyi County and adults' urinary iodine ( r s = 0.17, P < 0001) in Ningling County were positively correlated with water iodine. There was no statistically significant difference in the incidence of thyroid enlargement in children between Luyi County (0.8%, 2/240) and Ningling County (0.4%, 2/468, χ 2 = 0.80, P = 0.586), but the incidence of thyroid nodules in children in Luyi County (11.2%, 27/240) was higher than that in Ningling County (1.7%, 8/468, χ 2 = 27.36, P < 0.001). The incidence of thyroid nodules in pregnant women in Luyi County (23.3%, 28/120) was lower than that in Ningling County (46.5%, 33/71, χ 2 = 10.99, P = 0.001). There was no statistically significant difference in the incidence of adult thyroid nodules between Luyi County and Ningling County (χ 2 = 0.86, P = 0.354), with a ratio of 29.6% (71/240) to 32.9% (160/486). Conclusions:Providing population with non-iodized salt in iodine adequate areas, the overall iodine nutrition is at an appropriate level. However, children consuming iodized salt in iodine adequate areas have high level of iodine nutrition, and it is necessary to consider supplying non-iodized salt or reducing the concentration of iodized salt. Pregnant women in iodine adequate area should maintain the current policy of supplying iodized salt unchanged.
