I have a total of 4 weeks preop diet. The first 3 weeks, daily, I could have 2 protein shakes, 2 low cal, low fat, low carb snacks, 3 oz of lean protein, and one cup of non starchy vegetables. Also at least 64 oz water. I lost 22 lbs. this last week I can have 5 protein shakes and at least 64 oz water. I’m on day two of that and I have been very weak, shaky, and sometimes nauseous today. Hoping for a better day tomorrow!