Its the first week thats a killer, but decided not to do sole source (no food at all) I lasted a week last time Holly, but lost half a stone. So I'm doing step 2 where you have 3 CD's a day and a very low fat tea, ie 200 cals. Adds upto around 800 cals a day. Its not too bad once you get into it. You only have a stone to lose dont you..gosh you'd lose that in 3 weeks on the CD.