Cytose is a patented, Medical Food formulated from GRAS approved D-Ribose. The five-carbon sugar, D-Ribose or pentose, is found naturally in our bodies. D-Ribose is not like any other common sugar. D-Ribose provides the key building block of Adenosine Triphosphate (ATP), and the presence of ribose in the cell stimulates the metabolic pathway to synthesis this vital compound. If the cell does not have enough ribose, it cannot make ATP. So, when cells and tissues become energy starved, the availability of ribose is critical to energy recovery produced by mitochondria.