I am really amazed that some people are unsure of what the pre/post diet are and why they are SO important!
Preop---- 2 weeks of high Protein, liquids(meal replacement, not just slimfast or carnation inst) is needed to decrease the size of the liver, reduce the fat around it. During surgery the have to work around the liver and they must be sure to have enough room and avoid injuring it.
Post op---2 weeks High protein liquids--Banded area is sutured and those sutures need to HEAL. This diet allows that to happen.
Protein is important in the healing process, it help wounds/surgical sites to heal by increasing the bodys ability to build lean muscle.
Best of luck to all, I am currently in the middle of my required 6 month MD supervised diet and HOPE to be approved in late Feb 2010.