Sampling Survey And Study On Dietary Iodine Intake In The Different Urine Iodine Level Regions In Yunnan Province

Objective：To survey the urine iodine concentration, drinking water iodineconcentration, quantity of foods intake and salt intake, and to calculate thecontribution rates of all foods iodine intake and salt iodine intake to the total dietaryiodine intake in the surveyed areas. And then provide scientific proof to theadjustment iodine concentration standard in iodized salt.Methods: Yunnan province would be divided into3urine iodine level regions(higher than, average, and lower than urine iodine level of whole province) accordingto urine iodine monitoring data of in recently years; randomly sampled1county in the3urine iodine level regions (randomly sampled Mouding, Nanjian and Lianghe as3project counties for the survey) in each urine iodine level region, respectively, andrandomly selected3surveyed points (1urban point and2rural points) in each county,respectively, randomly selected30families to survey with successive3days24-hourdietary retrospective method and weighing method in each surveyed point,respectively. The calculation of the quantity of the all foods iodine intake according toChina Food Composition (2ndedition) and Food Nutrients Rapid Access, salt iodine intake quantity was calculated according to iodine concentration in iodized saltand the quantity of salt intake.Results:1. In general, the3counties’ Median of Urine Iodine (MUI)(p25-p75) of normalpopulation and special population (pregnant woman and breast-feed woman) was288.52（202.08—397.90）μg／L and238.75（143.79-361.97）μg／L, respectively. Thedistributions of urine iodine concentration there were not significant difference amonggeneral populations and special populations in3counties, respectively, but thedistributions of urine iodine concentration there were significant difference betweengeneral population and special population, and urine iodine concentration of generalpopulation was higher than special population s, the MUI of population in urban waslower than rural.2. In general, the3counties’ iodine concentration median (p25-p75) of theiodized salt was33.23（30.64—35.68）㎎/㎏.3.In general, the3counties’ drinking water iodine concentration median (p25-p75) was0.77（0.06—3.48） g／L, and93.90%drinking water specimens’ iodinecontent were lower than10μg／L.4. In general, the3counties’ salt intake quantity median (p25-p75) was9.1（7.5—11.2）g/person/day, rural residents’ salt intake quantity was higher than urbanresidents’, and male’s salt intake quantity was higher than female’s, salt intakequantities were different among different activity intensity groups, and the salt intakequantity would increase with activity intensity enhanced.5. In general, the3counties’ all foods iodine intake quantity median (p25-p75)was28.0（24.0—31.0）μg/person/day. 6. In general, the3counties’ total dietary iodine intake quantity median (p25-p75) was289.9（234.5—352.5）μg/person/day, and it was higher than recommendediodine intake amount that all age groups and physiological status groups surveyed inthis survey, and this difference had significant difference, rural residents’ total dietaryiodine intake quantity was higher than urban residents’, and the total dietary iodineintake quantity would increase with activity intensity enhanced too.7. In general, the contribution rate was90.30％that salt iodine intake quantity cto the total dietary iodine intake quantity in the3countiesConclusion：1. The iodine nutrition status of normal population was exceeding appropriatequantity and the iodine nutrition status of special population was appropriatequantity according to the analysis result of urine iodine, and the MUI of populationin urban was lower than rural.2. In the3counties, the drinking water iodine concentration was very lowgenerally that, and the drinking water iodine concentration median (p25-p75) was0.77（0.06—3.48）μ g／L, and93.90%drinking water specimens’ iodineconcentration were lower than10μg／L3. In the3counties, the salt intake quantity median (p25-p75) was9.1（7.5—11.2）g/person/day, rural residents’ salt intake quantity was higher than urbanresidents’, and male’s salt intake quantity was higher than female’s, salt intakequantities were different among different activity intensity groups, and the salt intakequantity would increase with the activity intensity enhanced4. In general, the3counties’ total dietary iodine intake quantity median (p25-p75) was289.9（234.5—352.5）μg/person/day 5. In general, the iodine intake quantity of population mainly came from iodizedsalt in the surveyed regions, and the contribution rate was90.30％that salt iodineintake quantity to the total dietary iodine intake quantity,6. Universal Salt Iodization (USI) will still be the main measure to preventionand control of Iodine Deficiency Disorders (IDD) in overall Yunnan province in thefuture, but the current salt iodine concentration was unreasonable, and it is urgent toadjust the current iodine concentration standard down in the iodized salt.