You know, I haven't heard about people going into ketosis while dieting on Atkins. (?)
I also don't think ketosis is exactly the right word for what happens when you fast. I've read a book by a doctor who explained it as "auto-(something)". Which is your body stopping digestion and starting a self cleansing, which includes eating away the dead/damaged/dying cells. As soon as I can piece my book together (if I even have all the pages) I'll know what the word is and better be able to describe the process. :) My daughter destroyed the book....
I'm going to look more into this word ketosis and see if is the "auto-something" process or just something similar, because people eating nothing but protein and going into "auto-something" doesn't make any sense. :)