PSMF is actually a very proven and legit (read hardcore)
diet that I would recommend to many of situations. Fasting in general is not a bright idea. Protein Sparing Modified Fast, now that is a different story. Good stuff to the original poster.
For those of you who are not familiar, see Lyle Mcdonald.
Also, for those who were against fasting, especially PSMF, please realize that people who have a large amount of weight to lose, their bodies don't follow the physiological rules that you are accustomed to discussing.