For being regular as clockwork. I use fiber capsules from Sam's club, the dose is 5 with big glass of water. I got dehydrated a few years ago and paid an awful price which included having a hemorrhoid surgically removed. No way am I going to let that happen again. When I travel, I make sure I stay hydrated and get my fiber pills- easier than trying to each that much fiber through salads etc. This is cheaper, easier and more portable than Metamucil IMHO.