In subjects with an underlying thyroid disorder (underlying autoimmune thyroiditis, previous treatment with radioactive iodine or history of external thyroid irradiation, previous subtotal thyroidectomy, postpartum or subacute thyroiditis and intake of some medications, such as lithium, which interferes with iodine organification and thyroid hormones release), acute excessive iodine intakes may lead to temporary overt or subclinical hypothyroidism that resolves when iodine intakes decrease [41]. Here, TG is linked to thyroid gland disorder.