I agree, take magnesium supplements. They keep me totally regular. All you need to do is up the dosage and stuff will flow like crazy.
Take it before you go to bed, the last thing you put in your mouth before your head hits the pillow. I recommend something that comes in capsules, as pills might not completely break down. I like Twinlabs. 2-4 capsules before bed. Most people could probably get by with 1, but you may have to up the dose to be regular.