>The RDA limits for vitamins and minerals were established after World War II. One of the last essential elements included in the RDA system was iodine, established in 1980 and confirmed in 1989. The RDA for iodine was based on the amount of iodine/iodide needed to prevent goiter, extreme stupidity and hypothyroidism. The optimal requirement of the whole human body for iodine has never been studied. Therefore, the optimal amount of this element for physical and mental wellbeing is unknown. Based on demographic studies, the mainland Japanese consumed an average of 13.8 mg daily and they are one of the healthiest people on planet earth. One tablet of Iodoral contains 12.5 mg iodine/iodide, an amount very close to the 13.8 mg average intake of mainland Japanese.<
http://www.health-science-spirit.com/iodine.html The Japanese also get more mercury, another ancient "wonder drug," in their diet than most but maybe not everyone thinks that is good.
Surely we could use most anything that helps prevent "extreme stupidity" in many citizens, notably our leaders, but much literature on the subject of dietary and medicinal iodine often seems to appeal best to that quality in the reader.
Best, Terry