They may or may not, but everyone's different and you should be delighted. I think it's reasonable (if you stick to plan for the most part) to assume you can lose 20 lbs. in about 3-4 months. You may lose 10 lbs. of that during Phase 1, and then the rest will slowly come off. One thing is to keep in mind you may not lose much the two weeks following your completion of Phase 1. Thats just your body catching up, and losing the real fat pounds that came off as water during Phase 1.