I don't understand your question. Do you not have a thyroid? Are you on thyroid medication?
There are two types of thyroid disfunctions. But if you get the correct dosage you wont gain weight. If you still have weight problems, try a hypnosis disc.
I used...thinkandlose.com and it worked for me. I am 140 for 3 years straight, on occasion I may lose a little or gain but it stays pretty much on the money.