OptiBac Probiotics For Everyday Extra Strength 30s is an advanced daily supplement containing high quality natural bacteria. Each capsule contains 20 billion live cultures, providing 5 extensively researched strains such as Lactobacillus acidophilus NCFM - the most researched strain of acidophilus in the world. This product is scientifically proven to pass through the stomach acids and survive the bile salts to reach the gut alive. What\'s more this supplement is free from sugars, fats and flavourings that may be found in other food & drinks containing live cultures. OptiBac Probiotics For Everyday Extra Strength is a formula aimed at those seeking an advanced, high strength, quality supplement.