I can attest to that. Before my final high school exams (oral - this is quite serious in our country) I drank a can of red bull - the first of my life. I was so

I can attest to that. Before my final high school exams (oral - this is quite serious in our country) I drank a can of red bull - the first of my life. I was so hyped that despite knowing everything I had trouble concentrating - I passed but without the red bull I'd undoubtedly have passed with better grades. Coffee still affects me strongly even though I now drink a cup a day. I also get a strong come-down effect so the net result is about even. Others I know drink coffee all day long and don't have a come down effect either.