PreticX Xylooligosaccharide (XOS) Prebiotic Clinically Validated to Nourish Intestinal Flora Prebiotic Bifido Boost Powder is an advanced prebiotic formula that feeds and encourages the growth of probiotic Bifidobacteria in the gut, helping to support a healthy balance of gut microflora. This product features PreticX, a unique xylooligosaccharide (XOS) prebiotic ingredient that nourishes existing probiotic bacteria, favorably changing gut microflora composition to promote healthy, balanced immune system function, regularity and intestinal comfort.