I have no idea. Have you googled? I would think it has some effect just like flouride does, but I don't know this for a fact.
I'll google too and see what's out there.
Now you've made me hungry. I could SO go for some shrimp scampi...
Lots of info out there!!! I googled "high iodine diet + thyroid" and got a zillion hits. I weeded through the first 2 pages and came up with:
http://www.jarvm.com/articles/Vol1Iss1/CASTIJVM.htm (puppies)
http://jcem.endojournals.org/cgi/content/full/83/3/765
http://biology.clc.uc.edu/courses/bio105/endocrin.htm
http://www.thyca.org/rai.htm
The first article is about puppies, but their physiology is comparable to ours. The last is in regard to RAI.
I've always heard if you crave some particular type of food, your body is telling you it needs something in that food ... ??? !!
I make a point to eat iodine, seafood, iodized sea salt etc - I too crave it - and I've read the dangers to your thyroid - etc - I eat nori papers wrapped around fish which are made from seaweed and I love seaweed salads from asian store - I also eat soy and drink it in my coffee everyday - I have always believed when you crave a food it's your body telling you to eat it - so I do - again, maybe not for everyone but I don't want to get hyper so I don't mind if iodine & soy interfere w/ my thyroid - maybe that's crazy but I feel great lately