Fasting is a wonderful way to lose the weight. It's more importantly, an excellent way to get back your health. Once the fast is over, you can't go back to eating badly. You've got to continue to eat healthy (with occasional indulgences) or you will gain back the weight. I know from experience. ;-) The nice thing about fasting is that afterwards, you really don't feel like eating badly anymore. I crave the good stuff more than any of the bad stuff right now. You're stomach is also smaller, so you don't and can't pack away huge amounts of food.
If you feel that you're being led to fast, make sure you're completely informed and have someone who really knows how to do it, nearby. I know I've said this before, but it's REALLY important. :)