Once you have the surgery, your doctor should continue to monitor you with thyroid function tests. If you have the entire thyroid removed then you will need some medication to replace what your thyroid use to do. Lets look at what the Thyroid does.

The function of the thyroid gland is to take iodine, found in many foods, and convert it into thyroid hormones: thyroxine (T4) and tri-iodothyronine (T3). Thyroid cells are the only cells in the body which can absorb iodine. These cells combine iodine and the amino acid tyrosine to make T3 and T4. T3 and T4 are then released into the blood stream and are transported throughout the body where they control metabolism (conversion of oxygen and calories to energy). Every cell in the body depends upon thyroid hormones for regulation of their metabolism.

The thyroid gland is under the control of the pituitary gland, a small gland the size of a peanut at the base of the brain. When the level of thyroid hormones (T3 & T4) drops too low, the pituitary gland produces TSH (Thyroid Stimulating Hormone) which stimulates the thyroid gland to produce more hormones. Under the influence of TSH, the thyroid will manufacture and secrete T3 and T4 thereby raising their blood levels. The pituitary senses this and responds by decreasing its TSH production. One can imagine the thyroid gland as a furnace and the pituitary gland as the thermostat. Thyroid hormones are like heat. When the heat gets back to the thermostat, it turns the thermostat off. As the room cools (the thyroid hormone levels drop), the thermostat turns back on (TSH increases) and the furnace produces more heat (thyroid hormones).

So you see the thyroid functions synergistically with the pituitary, so some form of treatment would be necessary if you have a Total Thyroidectomy. You most likely will gain some weight after having this surgery, but without thyroid medication you will not be able to control your metabolism and will most assuredly gain lots of weight, plus you could develop what is called a myxedema coma, a rare, life-threatening condition. These are the symptoms to myxedema comas: Mental deterioration such as apathy, confusion, and psychosis, extremely low body temperature (hypothermia), extremely slow heartbeat (fewer than 60 beats per minute), heart failure and respiratory failure which will lead to death if not treated. Good luck, Susu