Depends on your insurance and your surgeons requirements. Both my ins. and surgeon require a wt. loss of 5% of total body wt. before surgery, which starts with the weigh in at the initial surgeon evaluation appt. The 5% is required because that percentage is necessay to shrink the liver enough so that the surgeon can work around it easier. I think the ins. company wants to see if you can stick to a wt. loss plan.