Advanced Glycation End products (AGEs) are the result of a chain of chemical reactions after an initial glycation reaction. The intermediate products are known, variously, as Amadori, Schiff base and Maillard products, named after the researchers who first described them. Side products generated in intermediate steps may be oxidizing agents or not. "Glycosylation" is sometimes used for "glycation" in the literature, usually as 'non-enzymatic glycosylation.' AGEs may be formed external to the body (exogenously) by heating (e.g., cooking) sugars with fats or proteins; or inside the body (endogenously) through normal metabolism and aging. Under certain pathologic conditions (e.g., oxidative stress due to hyperglycemia in patients with diabetes), AGE formation can be increased beyond normal levels. AGEs are now known to play a role as proinflammatory mediators in gestational diabetes as well.