Land locked places,(switzerland for example) and places naturally deficient in iodine, (and in the days before canned goods) and places where you could not get sea food, all suffered from problems associated with iodine deficiency.

The body's reaction to a iodine deficiency is to first increase the size of the thyroid (since the thyroid needs/uses/regulates iodine use) this is called a goiter.

if a woman has a iodine deficiency, (evidenced by a goiter) she has very large chance of not having enough iodine for her own bodies needs, and will have none to spare to a growing featus. Brain damage is one obvious result, but there is also skeletal damage, and other organ damage, as well.

iodized salt is the same price genearly as plain salt. sea salt, (which is 3 times more expensive!) also contains enough trace amounts of iodine so that nowdays, it is very rare to see a goiter.

there is one school that says there were no neanderthals.. the people we call neanderthals were just early settlers, who were left isolated, and had no trading partners with less land locked peoples. the chronic iodine deficiency, lead to stunted growth, heavy jaws, and slopped head.. an the neanderthals were not 'killed off' by newer peoples coming to europe, but became less neanderthal like, as new people brought codfish, sea weeds and other iodine rich foods in to the areas of central europe were they lived.