Hello,
I'm only about two months out from surgery so I'm not an expert but you are correct about soda unless it is flat. You aren't suppose to drink from a straw either. You will have to make the consumption of protein and water a priority. If you get low on either your energy will be zapped, or at least that's how it did for me. You will also need to watch your carbs like if you were on the Atkins diet. The surgery is still worth things that we have to change. Good luck in making your decision.