Iodine, in turn, is the raw material used in the manufacturing of thyroxine T, the key thyroid hormone. 티록신 자체는 생물학적으로 더 활동적인 갑상선 호르몬인 트리요오드티로닌 T로 전환됩니다. Only about of triiodothyronine is actually formed in the thyroid gland, however.