Here's what my nutritionist wrote when I asked why the liquid diet was necessary and not just a low glycemic diet:
"You are to follow the pre-op meal plan that was given to you. I know it's hard because it doesn't consist of a lot of substance, but it is a requirement from Dr. --- in order to have surgery. Every person whom is overweight or obese has an enlarged liver. The liquid diet helps shrink the size of the liver, fat around the abdomen and helps Dr. -- perform the surgery in record time and prevents him from poking your fatty liver with his surgical tools. If your liver is fatty and it gets poked it will bleed and therefore the operation will take longer. Please follow the guidelines and don't have anything that isn't already listed on the pre-op diet. Dr. -- has been known to put his camera in the belly, look at the liver and if it's still too large, a funny color from eating solid foods or if he feels that you cheated, he will cancel your surgery on that very day! So please take full advantage of 2 Protein shakes a day and 3 servings of cottage cheese, milk or yogurt to help fill you up as much as possible. The previous items include protein for satiety! "
Guess that puts the fear of God (and Dr.--) in ME! I want my liver the right color, whatever that is!!