There is a nice FAQ on tea at http://www.enteract.com/~robchr/tea/faq.html.

The section on caffeine content follows:

        The amount of caffeine in a cup of tea varies tremendously, depending
        on the variety of tea and the brewing time. There is a great deal of
        contention about the caffeine content of various kinds of tea. Most
        people firmly hold the opinion that green tea has less caffeine than
        black, but a professional tea chemist has informed me that this is not
        true. Contrary to popular belief, green tea is likely to have just as
        much caffeine as black; and there is no reliable way of knowing in
        advance just how much caffeine is in your cup.

        I can report that the most caffeinated tea I have ever had was green.
        In 1995, I ordered a small pot of Yin Hao jasmine at a local
        coffeehouse, unaware that this delightful, high-quality delicacy was
        eye-popping, jaw-clenching rocket fuel. After two small cups, my hands
        were trembling and I could barely sit still. In fact, that same
        afternoon, I sat down and wrote this entire document in twenty-five
        minutes.

        [The last sentence is a joke. But everything else in the preceding
        paragraph is absolutely true.]

        The only way to know for sure how much caffeine you are drinking is to
        have each individual cup tested in a laboratory, which is not terribly
        practical if you intend to drink it. My advice is to pay attention to
        the tea you drink and judge it by how it makes you feel. There may be
        no better way to decide how to regulate your intake.

--
Brian Glass | [log in to unmask] | http://www.lni.net/bjg | 734-995-9022
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