First of all, I have to say fasting is a BAD idea! Heather explains it in The First Year. I think it is something to the effect of if you don't have something in your colon, it doesn't give the muscles anything to 'grip' causing spasms and pain. I THINK that's how it goes. I'm sure Heather will correct me if I'm wrong. Here's a past post on fasting by Heather: web page
The best thing for you to do is Break the Cycle. This includes beginning a fiber supplement.
Posts
Re: newbie
Here's a past post on fasting by Heather: 
