Iodine is a vital mineral virtually all of us are lacking if we are not supplmenting.  There are reasons for this (Please see my first link for an explanation).  Iodine and selenium work together and are very important for maintaining many areas of health, including thyroid, hormone regulation, heart rhythm regulation, and cancer prevention.  Iodine without selenium can be inflammatory; the balance of the two work together with glutathione in synergy to perform many "wondrous" health functions.