Iodine intaking pathway of Tibetan in Nangqian County, Qinghai Province

Objective To understand the pathway of iodine intaking among Tibetan, and provide basic data for prevention and control of iodine deficiency disorders (IDD). Methods Through the method of random sampling, the boarding and day student aged 8-10 and women of childbearing age were conducted dietary survey to understand the condition of food intaking via the 24 h review method in 2015. Samples of urine, drinking water, dried beef, milk, Qula and fried noodles were collected and tested iodine level. Results Due to taking iodized salt three times a day with meals, the median of urinary iodine among 492 investigated boarding students was 179.2 μg/L; differently, the median of urinary iodine among 298 day students in this investigation was 79.6 μg/L who taking iodized salt only at lunch at school; and in the study, the median of urinary iodine among 158 women of childbearing age who took iodine-free salt daily was 33.7 μg/L. The iodine contents in 51 drinking water samples, 66 dried beef samples, 48 milk samples, 20 Qula samples and 37 fried noodle samples were quantified respectively, and the average iodine contents of each food were 0.8 μg/L in drinking water, 59.1 μg/kg in dried beef, 61.5 μg/kg in milk, 226.4 μg/kg in Qula and 17.0 μg/kg in fried noodles. The acceptable daily intake (ADI) of iodine of the boarding and day students aged from 8 to 10 and women of child bearing age were 234.0, 126.4 and 76.7 μg/d, respectively,among which the ADI of iodine with iodized salt were 208.0, 78.0 and 0.0 μg/d. Conclusion Consuming iodized salt is a main method to get iodine among Tibetans in Nangqian County, so that it is significant to carried out this measure for a long time for free to let them have iodized salt every day instead of iodine-free one. Key words: Iodine; Urine; Food; Child; Women