Looking at what's contained in black tea, 20 mg, yes. I wonder if this helps explain the popularity of tea and the general idea that drinking tea helps you calm down.
Wikipedia suggests that longer brewing time is necessary to get the full dose of l theanine, for which I'd recommend a quality loose leaf tea, and reuse the leaves a couple times (make several cups consecutively in the same day).
My fancy loose leaf tea habit is about $6 a week, or about one latte with tax and tip. It's cheaper, fewer calories, and I don't get agitated like I occasionally do with coffee on an empty stomach. You still get away from your desk (which I think is half the point of going for a coffee anyway), but not for as long.
My dealer knows that some teas will keep you awake and some that won't. Some will have that info but maybe not know the connection with l-theanine.
Check out [San Francisco Herb Co.][1], quality bulk tea at great prices. This is how we curbed our tea expenses. You will need to buy $45 worth of product for them to ship, but they have a lot of oover great stuff --or get someone to go in with you on an order.
Though the other study I looked at found (for their samples at least) that black tea had more L-theanine than the green. (But I've seen the opposite claimed as well. So perhaps it depends on the particular variety and other factors.)
My fancy loose leaf tea habit is about $6 a week, or about one latte with tax and tip. It's cheaper, fewer calories, and I don't get agitated like I occasionally do with coffee on an empty stomach. You still get away from your desk (which I think is half the point of going for a coffee anyway), but not for as long.
My dealer knows that some teas will keep you awake and some that won't. Some will have that info but maybe not know the connection with l-theanine.