HI PJVB75 and welcome aboard the cambridge diet!!
The first week's losses are amazing and such a kick in the right direction! Im currently on day 14 and have lost nearly 1.5 stone!! (to be confirmed at WI tonight)
Days 1-3 are hard until ketisis kicks in as i'm sure you've heard but after that the days and weeks start to fly by and once you see the results you will be motivated anough not to cheat, plus the cost is enough for me to stick to it.
Good luck on your first day!! Hannah x