Like everyone's said, water is a HUGE part of the program, at least it is for me. I did MF back in the fall and I'm back here now, but when I did it the first time around it seemed like the days I didn't get TONS of water the scale was stuck, but when I chugged that water the pounds kept on coming steadily off! It's like, Medifast + Water + this forum = success!!
I usually fill my 64 ounce jug and make sure I drink it before I leave work. Then I chug more large glasses when I'm home at night also. It also really helped my skin also.