What causes thyroid hormones to be low?  Inflammation.  What causes thyroid hormones to be high?  Inflammation.  Why some people have low thyroid hormones and others have high thyroid hormones?  It's how their circulation and immune system reacts to the inflammation.  What causes thyroid inflammation?
What cures the thyroid?
Improving circulation and repairing immune system with Chinese medicine.  

https://rumble.com/v12i2my-best-diet-foods-juicing-and-supplements-to-cure-thyroid-hormones-and-inflam.html