Yea its a fad diest, it comes around about every 5 years.. From what I hear, you can eat as much of it and your don't gain any weight from it, but actually lose weight.. As with most diests there can be side effects, such as ""The Shits"" and you your health can suffer too as you are not getting all the normal vitamins and nutrients you should get eating a normal or balanced meal...
From my own experiences, I say cut you food intake wherever you can... Cut down on Fried foods, Chips, bread, Potatoes anything with batter or starchy, definitly cut down on Soda and other drinks heavy in sugar...
Drink a decent amount of water and depending on your current shape, walk/Run/Jog a mile or so each night or day... Increase the distance and pace as you can and you'll notice the difference... You have to keep it up to keep the weight off though..
I'm 6'5" 285LBS and I did the above this last summer.. I dropped almost 25 LBS, a pants size, and I could run further faster... I felt better and more energetic all the time... My several reasons my g/f really liked it too...
However, closr to winter, I got really sick and it seemed to last almost a month and I gt outta the habbit, so I'm right back where I was before.. I plan to start back up soon..