http://www.lef.org/magazine/mag2009/oct2009_Halt-on-Salt-Sparks-Iodine-Deficiency_01.htmIronically, health-conscious people are often most likely to develop iodine deficiency
Vegetarians also have substantially greater likelihood of iodine deficiency than carnivorous people, since foods of plant origin are less rich in iodine than animal-derived foods. One study demonstrated iodine deficiency in 25% of vegetarians and an incredible 80% of vegans, compared with only 9% of those consuming a mixed diet that contained meat.