'''Iodine''' is a [[chemical element]]. A trace element, it is required by humans for the synthesis of [[thyroid]] [[hormones]]. [http://lpi.oregonstate.edu/infocenter/minerals/iodine/]
+
'''Iodine''' is a [[chemical element]]. A trace element, it is required by humans for the synthesis of [[thyroid]] [[hormones]]. <ref>http://lpi.oregonstate.edu/infocenter/minerals/iodine/</ref>