FOS is a probiotic enhancing combination of the non-digestible carbohydrates, l-ketose GF2, nystose GF3, and fructofuransylnystose, which helps maintain an intestinal environment hospitable to beneficial microflora. FOS supports natural intestinal mechanical barriers, promoting gut integrity. Oral ingestion of FOS allows it to pass largely intact through the upper intestinal tract into the colon, where it is selectively utilized as growth nutrients by the beneficial bacteria, bifidobacteria and lactobacillus.