That's a good point, since our food supply has been unnaturally restricted thyroid-wise, for our protection by big brother.I believe it’s possible but I also see thyroid as something my ancestors consumed regularly and likely benefited from, particularly living here in a cold climate, so the idea of supplementing NDT indefinitely doesn’t bother me. To me, it’s like eating brains, liver, broths made from chicken necks and fish heads etc.