I have been drinking weak instant coffee since three days post op, about 3 cups a day, no espresso. I haven't had any problems so far. My guess is that most doctors tend to prohibit it because of stomach acidity and fluid intake. I take an anti-acid drug and i have no fluid intake issues, so things are ok. I have had about 8 espressos a day pre op and my doctors said that lots of over weight people are "coffee fiend" because of their lousy sleep, so i'm hoping that with the weight loss my sleep will get better and my desire for coffee (and cigaretts) will be reduced.