the weight loss may be the adrenals kicking in to compensate for the thyroid hormones, or lack of such.
iodine is needed for both hypo and hyper thyroid. you may get some reaction at first that you dont like but it will turn around.
you also need boron. 9mg of twinlab's triboron per day.
if Iodine alone wont get your thyroid going then you may need to take thyroid hormones. synthetics are out. armour is hard to get from doctors. i highly recommend getting nutrimeds porcine thyroid gland. it has everything - the nutritional support of the whole gland and the thyroid hormones found in armour, but not concentrated. thats your next step after trying Iodine for a while.