The living friendly bacteria in FIRST DEFENSE Probiotic Supplement are comprised of our unique blend containing Lactobacillus acidophilus, Bifidobacterium bifidum and Streptococcus thermophilus. We custom blended these super strains for their collective ability to guard against gas and bloating, to improve overall digestion, to maintain regularity and to support whole body health. Unlike other probiotics, each capsule of FIRST DEFENSE Probiotic Supplement contains 40 billion live organisms at time of manufacture guaranteeing that you are sufficiently repopulating your healthy bacteria daily.