Biblioteca Virtual en Salud

Objective To analyze the iodine nutritional status of children and pregnant women in Liaoning Province,and the iodine content of edible salt suitable for iodine nutrition level,to provide a basis for adjusting the suitable salt iodine content standard of key population.Methods In 2015-2018,a cross-sectional survey method was used to conduct iodine nutritional status surveys in counties (districts) within the jurisdiction of Liaoning Province.One township (community) was selected in each county (district)according to the east,west,south,north,and middle directions.Forty children aged 8-10 (age and gender distribution balanced) and 20 pregnant women were selected in each township (community),urine and household salt samples were collected from children and pregnant women,to test urine and salt iodine levels;and the water samples from all township (community) water supply plants in the province were collected for water iodine detection in 2017;and all respondents were calculated the dietary iodine intake.The multi-order linear curve was used to fit the salt iodine content suitable for children and pregnant women.Results A total of 1 549 townships (communities) were surveyed,including 1 125 centralized water supply townships (communities) with water iodine ＜ 40 μg/L;50 820 children aged 8-10 and 26 707 pregnant women were selected from the centralized water supply towns.The average iodine content of edible salt was 24.0 and 23.9 mg/kg,respectively.The median urinary iodine level of children was 168.5 μg/L,at the appropriate level of iodine;the median urinary iodine level of pregnant women was 137.8 μg/L,at the deficiency level of iodine.The average dietary intake of iodine in children was 228.4 μg/d,which was 3.51 times of the standard iodine requirement (EAR,65 μg/d) and 2.54 times of the recommended intake (RNI,90 μ g/d).The average dietary intake of iodine in pregnant women was 273.4 μg/d,which was 1.71 times of the EAR (160 μg/d) and 1.19 times of the RNI (230 μg/d),and 21.4％ (5 728/26 707) of pregnant women had lower iodine intake than RNI,the iodine intake was insufficient.After multi-level linear curve fitting combined with monitoring data,the iodine content range of edible salt in children's urine was suitable and the iodine intake in RNI-tolerable intake (UL,300 μg/d) was 13-25 mg/kg (20 mg/kg + 20％);the iodine content range of edible salt in pregnant women's urinary iodine was suitable and the iodine intake in RNI-UL (600 μg/d) is 25-37 mg/kg (31 mg/kg + 20％).Conclusions Under the current salt iodine content standard (25 mg/kg) in Liaoning Province,children's iodine nutrition is generally at the level of iodine appropriate;pregnant women's iodine nutrition is generally at the level of iodine deficiency.It is recommended that all regions should revise the iodine content standard for edible salt in due course in combination with the iodine nutritional status of key populations within the jurisdiction.