What you are talking about is a huge reason I went cg. My thyroid issue actually ended up as cancer. After my thyroid was removed, the doc took me off all meds for about 7 weeks so I could take radioactive iodine. After that, I went back on the synthroid at a much higher dose. The goal is to keep my slightly hyperthyroid all the time. My hair hasn't been the same since. It is so dry and was thinning. So I started the cg method, and the hair breaking and falling out abruptly stopped. I seem to have to break some of the norms to keep my hair happy. I have to use gobs of co wash condish, and I have short hair. Stuff like that. I don't know. Play with your routine. I need more moisture than I should and lots of protein.
2a canopy with 2b underneath.
Fine hair, low elasticity,
Hair dislikes oil
Live in dry climate