The thyroid gland is the only source of thyroid hormone in the body; the process requires iodine and the amino acid tyrosine. The gland takes up iodine in the bloodstream and incorporates it into thyroglobulin molecules. The process is controlled by the thyroid-stimulating hormone (TSH, thyrotropin), which is secreted by the pituitary. Not enough iodine, or not enough TSH, can decrease thyroid hormone production.
the thyroid gland is the only source of thyroid hormone in the body; the process requires iodine and the amino acid tyrosine the gland takes up iodine in the bloodstream and incorporates it into thyroglobulin molecules the process is controlled by the thyroid-stimulating hormone (tsh thyrotropin) which is secreted by the pituitary not enough iodine or not enough tsh can decrease thyroid hormone production