Please dont follow these fad diets that just damage your bodily system.
I tried this ....desparate to lose Kgs...recommended by experienced person.
I can diet hard but for this couldnt make it more than 6th day.
Banana day is worst....headaches ..whole day bcos of bananas.. you wont eat bananas for 2 months after this diet.

I worked out also for initial 3 days but starved body wont let us excercise so stopped later and no significant difference in wt (0.6 lb less

)
Why do people lose weight with these diet?
There is nothing magic...in any kind of wt loss program.
When we start starving our body ,suddenly lesser calories coming in, first of all water weight will go and then fat & muscle loss..
If we starve our body for longer, body wd get used to of low diet and slow down metabolism ,thus no-weight loss.
But as soon as diet is over, water-weightcms back.
I think eating healthy and low cal (in the beginning-to trigger weight loss) and workout is easier than starving and living 7 days with headaches.