Hi great question. Basically there is soluable and insoluable fiber. One is for bulking and the other is for expelling waste and keeping the arteries clean. You need both for a health body. Fiber is fiber and it can come from different sources. The best of course is from natural sources like fruits, veggies (5 prunes a day work very well and you get the antioxidants with it). Ground Flax seed is also good. (2 tablespoons a day at different times or sprinkle over cereal. Doesn't have a bad tastes or anything, will keep your heart and brain healthy too-rich in omega 3's). If you don't have time for that I recommend wheaties and ULTRA-FIBER tablets that are made from fruits and veggies. It keeps your colon clean which automatically increases you metab., helps flatten the tummy and helps you loose weight. Hope that helps.