Analysis of iodine nutritional status of population before and after adjustment of salt iodine content in Tianjin / 公共卫生与预防医学

ABSTRACT

Objective To study the iodine nutritional status in the key population in Tianjin before and after the implementation of the new standards of iodized salt content, and to provide a scientific basis for iodine supplementation. Methods According to the method of population proportion sampling, the family edible salt samples, the urinary iodine and goiter of children aged 8-10 years and the urinary iodine level of pregnant women were investigated before the adjustment of salt iodine content (2005, 2011) and after the adjustment (2014, 2017). The results were compared and analyzed. Results The median of salt iodine after the adjustment (26.05mg/kg) was significantly lower than that of before (30.20mg/kg, Z=12.867, P2=221.916, 309.405, 540.148, respectively, P 2=0.196, P=0.658). After stratified analysis based on salt iodine content, it was found that among children who took iodized salt and qualified iodized salt, the median urine iodine after adjustment was lower than that before adjustment, and the difference was statistically significant (Z=2.726, 2.742, all P2=4.769, P=0.029). Conclusion After adjusting the salt iodine content in Tianjin, children's iodine nutrition was optimized from a higher level to an appropriate level, and thyroid goiter rate of children remained at low level. The iodine nutrition of pregnant women was slightly lower than adequate level, but the proportion of pregnant women at the adequate level increased. The new standard of iodine salt was appropriate, but the proportion of children with urine iodine <100μg/L increased, which needs to be monitored. At the same time, the iodized salt coverage rate and the qualified iodized salt consumption rate did not reach the elimination standard of iodine deficiency diseases, and the supervision of the salt industry market should be strengthened.