There are many people that will tell you different natural options try a Naturopath that has a good reputation as they are not cheap. I have a under active thyroid and had tried natural and you have to be careful what you take and remember to still get your thyroid tested.

I cannot believe no one has answered you. There is only one book you need to read it is called “Thyroid healing” by Anthony William, see if your local library has it. It will change your life.