I have never done anything like it either and couldn't even imagine with out eating any food for part of a day...I thought about food, but I was so okay, the first few days I really needed to be strong and stick to my plan, but after awhile it really got easier...
My day 9 and 10, I wasn't even hugry for the drinks, had to force myself so i would have my energy so I could be active and go to the gym...
If i can do it, anybody can really do it...
Be careful and ask your doctor if it is the right thing for you to do though...
Love11