In 19th and early 20th century medicine and psychology, an "idiot" was a person with a very severe mental retardation or a very low IQ level, as a sufferer of cretinism, defining idiots as people whose IQ were below 20 (with a standard deviation of 16);
In current medical classification, these people are now said to have profound mental retardation, and the word "idiot" is no longer used as a scientific term.
Iodine deficiency disorders are of great concern because they have a brutal impact on up to a quarter of the world’s population, however fortunately it is one of the easiest of the most common deficiencies to control. Iodine deficiency disorders manifest in several forms, depending on the time of onset. When a fetus is deprived, it often results in cretenism or mental retardation. Children without Iodine often suffer from retarded physical growth and intellectual development, as well as from goitre. Adults suffer from goitre and sometimes stillbirth or spontaneous abortion in pregnant women. Those outcomes that are visible, such as goitre and cretenism, are easily detected clinically and are use diagnostically for IDD. The subtler effects that come from deficiencies, such as slightly enlarged thyroid gland, hindered psychological development, stillbirths, and spontaneous abortions are less easily detected or attributed to IDD.
i declare that the population of the US that has subclinical Iodine deficiency is in the 90 percentile range. add to that fluoride, mercury and lead and what do you get?