Think I had too much of it before and my body just straight out rejects caffeine now... Basically, some 6 years ago I started noticing that I got a tiny bit dizzy almost every time I drank coffee, but I didn't think much of it. Then, one day I had a light breakfast and a cup of coffee at the hotel bar in the morning, went back to my room, and about 20 minutes later, I felt so ill I thought I was having a heart attack dizziness, extreme weakness, knot in the stomach, cold sweat, heart pounding, tunnel vision... Drank like 3 liters of water in the next half hour to flush it all out, and then all was more or less back to normal, although I still felt tired for the rest of the day. After that, I didn't drink any coffee for about half a year, tried it afterwards (just a few sips), and got that light dizzy feeling again, so I stopped completely. I do drink decaf from time to time now, but it's not the same So it's just water for me now.