A synbiotic nutritional supplement containing fructooligosaccharides (FOS), which are linear chains of fructose units that are linked by beta (2-1) bonds, and probiotic cultures of Lactobacillus paracasei (L. paracasei), L. rhamnosus, L. acidophilus and Bifidobacterium lactis (B. lactis), with gastrointestinal (GI) protective and immunomodulating activities. Upon oral administration, the bacteria in this probiotic supplement help maintain adequate colonization of the GI tract and modulate the composition of the normal microflora. Upon colonization of the GI tract, the probiotic bacteria form a protective barrier that helps maintain the integrity of the epithelial barrier. This will interfere with the attachment of pathogenic bacteria and other harmful substances, prevent inflammation and improve GI function. Additionally, the reconstituted microflora may metabolize FOS, which may promote calcium mobilization into the bloodstream by maintaining a neutral pH in the lower gut.