Too much tea?

About two months ago I stopped drinking coffee (more or less--I was drinking around half a pot a day and now I might have a cup in the morning, about a third of the time), and started drinking tea.  Right now I'm drinking ~5 cups a day of tea or so.  At night I have earl grey, and the rest of the time it is plain black tea.  I don't add milk or sugar, and tend to brew it strong.

I thought it was healthy (or at least relatively harmless), but I read that too much tea causes excess fluoride to build up in the thyroid gland.  Am I drinking too much?  I know of the danger of dehydration with caffeine, but I make sure that I am properly hydrated so that isn't a problem.

[Paxiled]

Switch to green or white tea.  Much more balanced with antioxidants and relaxants.  Since most people in the world drink a lot of green tea and some a lot of black tea and some in between (India and vicinity) it's unlikely to be harmful.  But try to buy organic, and again, green will be better for you.  Hard to see how it could deydrate you, first that's hard to do from a medical standpoint, and second, tea is mostly water.

[allmymarbles]

I asked my father (a chemist) some years ago why people who could not tolerate coffee because of the caffeine were able to drink tea, which also had caffeine. He said there was a difference in the caffeine, that tea caffeine had an extra molacule. He also said that while some in the medical community said tea-drinking wasn't any better than drinking coffee, it was irrational for them to assume that millions of people in the world who said tea did not have the same ill effect on them as coffee were delusional. So, so much for caffeine.

But I notice that you are not moderate in your habits. You used to drink a lot of coffee and now you drink a lot of tea. I should think that anything you eat or drink in excess would not be good for you.