Wikipedia says:
"Thus iodine deficiency, as the single greatest preventable cause of mental retardation, is an important public-health problem."
"Iodine deficiency is one of the leading causes of preventable mental handicaps worldwide," http://en.wikipedia.org/wiki/Iodine_deficiency
"Some estimates suggest that nearly 20 million infants may be at risk for brain damage or mental retardation due to low iodine during the mother’s pregnancy [Source: Hetzel]. Proper amounts of iodine are needed for growth and development of the brain. Other conditions linked to low iodine include ADHD, pregnancy loss, multiple sclerosis, Alzheimer’s disease, Parkinson’s disease and other nervous system diseases [Source: Boyages, Foster]." http://health.howstuffworks.com/wellness/food-nutrition/vitamin-supplements/i...
I continue to be amazed by the wide range of health problems cured with iodine. No wonder the drug companies are doing their best to censor, belittle & prevent med schools from training on it.