Prebiotics are nondigestible food ingredients that stimulate the growth and/or activity of some bacteria, like bifidobacteria, in the colon...they escape digestion in the upper GI tract. FOS is a prebiotic. So prebiotics are food for bacteria that are in your body.
Probiotics are supplements with good bacteria or yeast. So I guess VSL#3 would be a probiotic. I loosely call yogurt a probiotic, but I guess it's really the good bacteria in it that are probiotic. So probiotics add good bacteria to your body.
Post Edited (njmom) : 10/8/2007 11:01:19 PM (GMT-6)