The main hormones produced in your thyroid gland are thyroxine (T4) and triiodothyronine(T3). They influence the speed at which your body processes and uses energy(your metabolic rate). Hyperthyroidism(overactive thyroid) and hypothyroidism (underactive thyroid) are common problems associated with the levels of T3 and T4.Another hormone called calcitonin is produced in your thyroid gland. Calcitonin works with the parathyroid hormone, which is made by the parathyroid glands. Together they help to control the amount of calcium in your body, which is important for healthy bones and nerves.
Attribution: BUPA