Xu Jing, Liu Shichuan, Ma Wei, Li Xiuwei, Guo Min, Cao Xiaoxiao, Gu Yunyou, Wang Haiyan, Wang Jianqiang, Zhang Ying, Zhuang Guangxiu, Liu Liejun
Chinese Center for Disease Control and Prevention, Key Laboratory of Trace Element Nutrition of National Health Commission of China, National Institute for Nutrition and Health, 155 Changbai Road, Changping, Beijing, 102206, China.
Hangzhou Center for Disease Control and Prevention, 568 Mingshi Road, Jianqiao Town, Hangzhou, 310021, Jianggan District, China.
Thyroid Res. 2022 Mar 19;15(1):4. doi: 10.1186/s13044-022-00122-8.
The residents of both the agricultural and pastoral areas of Tibet share the same iodine deficiency and iodine nutrition, but the rate of thyroid goiter was significantly higher in the agricultural areas than in the pastoral areas. This project sought to determine why the populations in the iodine-deficient pastoral areas show a lower rate of thyroid goiter.
Food frequency questionnaires (FFQs) and 24 h history recalls were adopted to investigate the dietary patterns of the residents of the agricultural and pastoral areas. Meat and milk samples were collected to measure their inorganic iodine, total iodine and thyroid hormone contents using ICP-MS, As-Ce catalytic spectrophotometry and the Siemens' chemiluminescence method, respectively. The intake of protein, and the microelements, selenium and iron, was calculated according to their content in the food.
The per capita daily intake of meat, dairy, and cereal in the pastoral areas was 116.7, 216.7, and 433.3 g, respectively, which are significantly higher than those in the agricultural areas (50.0, 72.2, and 375.0 g, respectively) (p < 0.05). The content of thyroid hormone in dried beef and milk in the pastoral areas was 62.6 and 13.5 μg/kg, respectively, which was significantly higher than those in the agricultural areas (25.1 and 4.1 μg/kg, respectively) (p < 0.05). The daily intake of thyroid hormone, protein and microelements, selenium and iron from foods by the residents of the pastoral areas were 10.5 μg, 99.6 g, 30.0 μg and 15.8 mg respectively, which was significantly higher than those in the agricultural areas (1.79 μg, 56.5 g, 23.8 μg and 13.2 mg, respectively) (p < 0.05).
The significantly high intake of the food-borne thyroid hormone by the residents of the pastoral area could be the main reason the residents in the pastoral areas show a lower rate of thyroid goiter than those in the agricultural area. Moreover, the relatively high intake of protein and trace elements, selenium and iron by residents in the pastoral area could be another important factor for reducing the goiter rates.
西藏农牧区居民碘缺乏及碘营养状况相同，但农业地区甲状腺肿患病率显著高于牧业地区。本项目旨在确定碘缺乏牧区人群甲状腺肿患病率较低的原因。
采用食物频率问卷（FFQ）和24小时膳食回顾法调查农牧区居民的饮食模式。分别采集肉类和奶类样本，采用电感耦合等离子体质谱法（ICP-MS）、砷铈催化分光光度法和西门子化学发光法测定其无机碘、总碘和甲状腺激素含量。根据食物中的含量计算蛋白质、微量元素硒和铁的摄入量。
牧区人均每日肉类、奶类和谷物摄入量分别为116.7克、216.7克和433.3克，显著高于农业地区（分别为50.0克、72.2克和375.0克）（p<0.05）。牧区牦牛肉干和奶类中甲状腺激素含量分别为62.6微克/千克和13.5微克/千克，显著高于农业地区（分别为25.1微克/千克和4.1微克/千克）（p<0.05）。牧区居民通过食物每日摄入的甲状腺激素、蛋白质、微量元素硒和铁分别为10.5微克、99.6克、30.0微克和15.8毫克，显著高于农业地区居民（分别为1.79微克、56.5克、23.8微克和13.2毫克）（p<0.05）。
牧区居民通过食物摄入的甲状腺激素显著较高，可能是牧区居民甲状腺肿患病率低于农业地区居民的主要原因。此外，牧区居民蛋白质和微量元素硒、铁的摄入量相对较高，可能是甲状腺肿患病率降低的另一个重要因素。
