D-mannose is a simple sugar and a very close relative of glucose. The human body produces very small amounts of D-mannose but overall it is an extremely insignificant amount. Supplements like these therefore provide you with a convenient way of getting D-mannose in to your system. This simple sugar, which has a sweet taste, is also found within fruit like cranberries. These handy tubs, which contain 30 tablets, are great for storing within a kitchen or bathroom cupboard if you wish to have a ready-supply of D-mannose in your home.