I am grateful that Kaiser required 6 weeks of classes prior to my sleeve surgery. It helped me to understand why I crave things and what the cravings are related to in the long run. I found the food/activity diary to be indespensible as well to help me make sure that I ALWAYS had a calorie intake deficit every single day. Addtionally, the diary made sure that I was eating enough protein! My surgery was in 2011 and so far I'm down 140! The lessons that I leared in the classes I apply on a daily basis to keep me on track. :-)