My wife was reluctant and sceptical. I convinced her that she should give up Slimming World, save herself £5 per week and stop feeling like food is her enemy. She fasted diligently and 4 weeks later she was a pound heavier than when she started. (I tagged along for support and I was also a pound heavier although I skipped a couple of fast days, my BMI is only 22).
I came on here to find out what could be going wrong and the message here seems to be "be on a diet for 5 days and be on even more of a diet for 2 days". So, my wife restricted her calories and lost half a pound. "Stick with it", I said. Week 6 brought a 3 pound loss, hallelujah! Week 7? A 2.75 lb gain. Overall loss over 7 weeks = half a pound.
Week 7 probably went wrong because we went out for an Indian meal with friends on Sunday evening. If we can't do that then this really is pointless.
Here's my conclusion, for what it's worth. If you "eat as you normally would" and fast for 2 days you are clearly going to lose weight. What you cannot do is come off a dieting regime and eat normally on 5 days and fast on 2. I have read here that there is no magic. I agree, it's just a shame that the TV program and book do seem to be selling something quite magical.
This is clearly working for many of you, may you continue to have success. My wife is going back to Slimming World where she will diet normally for 7 days a week rather than dieting moderately for 5 days a week and dieting severely for 2.