This Natures Probiotic has multiple different strains of stabilized probiotics, with 35 billion CFU/g per serving. Also added is a Pre-Biotic called Xylo Oligosaccahride which acts as food for the friendly bacteria and aids in growth. This pre-biotic helps withstand the bile salts and acidic conditions of your digestive system. Natures Probiotic helps establish/replenish your probiotic lining. The probiotics arrive on location where they are most needed to effectively replenish the mucosa lining and support your immune system.