On your question about supplementation, you'll probably want more than just fish oil with the iodine. You'll need the companion supplements--VERY important! If you haven't read about these yet, start with the FAQs and also use the search feature. At the very least, you'll need selenium, and these are also highly recommended: B vitamins (two of them, specifically), vitamin C,and magnesium.
Another thing to keep in mind about weight, sometimes while the body is detoxing, the weight *might* go up a bit. One of the body's ways of dealing with the toxins and protecting the body is encapsulating them in fat. Perhaps this happens less in people whose elimination systems are working better (liver, kidneys, colon, skin, lungs).