I have developed a high tolerance and it hasn't been healthy. Then getting off of it has been hard. I chalk that more to the frequency and the comforting habits than the quantity through. It's almost like a cigarette to me. I get the thought of reaching for coffee a hundred times a day. It must be a coping mechanism at this point or as you point out part of the anxiety.Agreed. But on the flip side, I also find exercise does a lot to mitigate the negative effects of caffeine. If I'm running and/or lifting, I can have at least 3 cups a day before I start to notice lower quality sleep or anxiety creeping in. If I'm just sitting around all day working on my computer and teaching, two cups is pushing it...