One of the common cause of this kind of desorder is too little iodine in the diet and here in Italy, since the 2005, we have a law about the dietary iodine in the school to prevent the thyroid desorders.
True, but itality is very close to the sea so you guys should get plenty of iodine, and if not, I think most table salt is alrdy enriched with iodine too, iodine is great not only for the thyroid but also for the brain.
I guess your family has some bad Thyroid producing genes...
Yes, my family seems to have a bad genes and talking with my endocrinologist he told me that in my area (I live in Tuscany, but not close to the sea) there are more people with this kind of problems than in other areas. The researchers think one of the reason of the higher % in this area was because the Chernobyl cloud after the disaster during the 1986, they are studying the effects in a long time.