This is one topic that has a huge range of responses. My paperwork says that it should be avoided because caffeine can be an appetite stimulant and stomach irritant. This is the ONLY rule I have broken in my post-op diet - I have half a cup of coffee and a cup of fairlife milk with a scoop of protein powder every morning for breakfast. I have not experienced any change in hunger levels (I have none) nor have I had any stomach irritation or excess acid problems (I do take a daily PPI, but not because of the coffee, it's something prescribed to all my surgeon's patients for the first 6 months), and my surgeon and dietician are aware of my choice and are pleased with my results so far. 

Have you asked your surgeon or dietician what their opinion is, and why?

I am pre-op and currently am gluten intolerant and have issues taking vitamins where it feels like someone punched me in the stomach and then inflated by stomach.  

Does the gluten issue continue post-op?  If vitamins are hard on you stomach now - does it get better post op?

I am over 9 years out from gastric bypass. I have maintained a 170#weight  loss for over 8years. My issue is that I still get dumping syndrome daily. Is this normal after all these years. This whole last week has been just horrible. I have to lie down after eating. Very challenging when at work. Anybody else still dump after all these years? Any good solutions, please let me know.

I has VSG and its ok on my plan.  Check with your team.

Try to eat balanced healthy diet including all kinds of healthy ingredients. You should eat leant meat, leafy greens, salmon, whole grains, nuts, berries, beans, fruits etc . Workout is important but you need to do both cardio and weight training. Any one of these will cause slow weight loss. Hopefully, you'll loss your extra weight soon. Drink lots of water and the use of super foods like green tea with lemon, lean red meat, cinnamon, avocado, berries can be very helpful for you in losing weight quickly.