Iodine-Deficient Vegetarians
According to this study, strict vegetarians and vegans “comprise probably less than 0.1%.” Focused on nutritional issues, the study found that iodine deficiency does not appear to be prevalent among the vegetarians and pregnant women included in this study.
The adequacy of iodine nutrition has not been studied among the vegetarian population, and field studies indicate that vegetarian diets do not lead to iodine deficiency and that vegans may suffer from excess iodine intake. There is insufficient evidence of whether or not iodine-deficient vegans or pregnant women are present in the United States.
http://www.ncbi.nlm.nih.gov/pubmed/15896441
