The formation of AGEs occurs from the reactive nature of reducing sugars (i.e. glucose) to undergo nonenzymatic rearrangements with amino groups of proteins and DNA to form irreversible cross-links. This non-enzymatic reaction of reducing carbohydrates with lysine side chains and N-terminal amino groups of macromolecules (proteins, phospholipids and nucleic acids) is called the Maillard reaction or glycation. The products of this process, termed advanced glycation end products (AGE), adversely affect the functional properties of proteins, lipids and DNA. AGEs and their adducts with proteins appear to be formed together in serum and tissues. AGEs have been established as one of the major factors responsible for the multi-organ damage in diabetes and aging.