on a number of occassions but I don't drink it regularly. It's really tasty! And yes, it will affect you kind of like caffeine. Just don't expect a jolt like you'd get from a strong cup of coffee (it's probalby more of a black tea-ish jolt ) But I remember Heather recommended it to a truck driver with IBS on the boards a while back to help him stay alert while driving late nights - so it must do something significant!
Another thought - are you getting enough protein in your diet? Whenever I find that I'm getting really run down despite eating seemingly well/exercising/drinking water etc. it's usually a sign that I need to have some more protein. Just a thought!
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I've had it before...
) But I remember Heather recommended it to a truck driver with IBS on the boards a while back to help him stay alert while driving late nights - so it must do something significant! 
