Where did you come across the info about green tea blocking the thyroid function? So far the only info I can find is that it may be harmful when taken in large amounts - more than 2 cups a day.
I do want to thank you for posting about this, as in my reading I just found out that my taking of green tea extracts is most likely why my bone density test came back much improved & my cholesterol levels were down!!!
Traveler, we have discussed this several times on another forum (a thyroid forum). I believe it is the tannins in the tea and it is all teas, not just green. Google tannins and thyroid, I came up with quite a few references. There was something else I mistakingly came across that had tannins recently, wish I could remember what it was - it surprised me completely.
I get my green tea extract in my multi - AOR ortho core. They are a very well reputed company (and I am very picky about my supplement recommendations. I research fillers, sourcing, etc.)