碘缺乏对胎儿及儿童的智力和身体发育有着深远影响,严重缺碘可产生克汀病。有几种适应措施可保护机体免遭碘缺乏的有害作用,即机体捕捉碘的能力增加,甲状腺内碘代谢改变,在消耗T_4合成的基础上增加T_3的生成量。甲状腺激素的这些变化受TSH控制,而血浆T_4减少启动了TSH的释放。缺碘时甲状腺激素合成上的这些变化的结果 Iodine deficiency has far-reaching effects on the intellectual and physical development of the fetus and children, and severe iodine deficiency can produce cretinism. There are several adaptations that can protect the body from the detrimental effects of iodine deficiency, that is, the ability of the body to capture iodine increases, the iodine metabolism of the thyroid changes, and the amount of T_3 produced on the basis of T_4 synthesis. These changes in thyroid hormones are controlled by TSH, whereas a decrease in plasma T 4 initiates the release of TSH. The result of these changes in thyroid hormone synthesis on iodine deficiency