I lost 80 lbs pre op. I followed what I learned in the classes. First I cut out all liquid calories. Pretty much only drank water. (Crystal light packets are ok). Protein, protein and more protein. I cut my carbs way back and more than anything I cut my portion size way back. I would eat a good protein packed breakfast, a sensible lunch and a small supper (protein shake/bar or a small salad). I also tried not to eat anything after 6:30/7:00 in the evening. I was able to go from 350 down to 270 lbs. My surgery is scheduled for the 29th of Oct and I am currently on the pre op liquid diet.