Yes, I agree with Chris and also want to add from my personal experience...
It is ok to fast IF u do have a tendency to control ur eating/impulsive eatings even after a very short fasts or/ and really understand the importance of eating THE RIGHT food especially after prolonged (long) fasts are over. If not then think twice.
I did two 10 dayers couple of years back and as soon as I finished the very first one, I was eating right till day 8 and then ate spagetty with a sourse and a chocolate too - I felt sooo bad that my friend was about to call an ambulance! So the right (and not in big amounts\0 food and for the right number of days are of VITAL of importance! Please bare it in ur mind.
And also please take into consideration that going at lower pace is in most cases far better and safer than trying to get the results very quickly. I remember myself, a few years back I was doing attempts of fasting for so many years just to understand for me the best way was and is just to stick to right eating habbits. With this I got better results than for so many years of my trials to fast. I think it is all up to individual. Just be Honest to Urself of what u truly can get and what u can loose from it (healthwise). All the best to u, dear. :)