TG and hypothyroidism: In this study, the increase of TSH was observed in subjects exposed to excess iodine; it did not increase the levels of free thyroid hormones, which coincides with some studies that relation this effect to the thyroid compensatory mechanism, which is characterized by enlargement of the thyroid gland (acute phase of the Wolff–Chaikoff effect) and that, after the withdrawal of excess iodine, TSH levels can decrease or hypothyroidism may occur [23].