Galactooligosaccharides (GOS) are a group of carbohydrates made up of a chain of galactose units. They are made from lactose and are similar in structure to carbohydrates found naturally in human breast milk. Their unique chemical structure enables them to escape digestion both in the stomach and the intestines, allowing them to pass undigested into the large intestine, where they act as prebiotics, stimulating the growth and activity of beneficial bacteria. Ariya Purity Galactooligosaccharides (GOS) has a higher purity than most on the market. The unique process of nanofiltration, concentration and drying results in a GOS concentration of no less than 70%, 20% higher than other popular brands. The higher purity also means it contains fewer and lower concentrations of contaminants such as lactose, glucose and galactose.