I decided to increase my vitamin D intake to 4,000 units a day from 2,000. Vitamin D is so important, and I don't get much sun.

http://www.vitamindcouncil.org/

I have suffered from constipation on and off over the past few years, but lately I noticed that if I take around 300 mg of magnesium at one time, within around 2 hours or so I am able to use the bathroom. This amount is good enough to let me use the bathroom without giving me diarrhea.