I'm 7 days post op. By doc is just fine with caffeine. I have gone from 3-4 espressos (black, no sugar) down to just one. I get down 3/4-1 oz tiny sips at a time and then dump the rest into my morning protein shake. Haven't felt the need to expand caffeine intake but cold brew + protein sounds good. I bought a bag of chike before surgery but I'm been doing almost 0 carbs/day so far and see no reason to add that in before stage 2/3.