Methylglyoxal: its presence in beverages and potential scavengers.

Nonenzymic glycation, also known as the Maillard reaction, is a complex series of reactions between reducing sugars and amino compounds. Previous studies have demonstrated that reactive dicarbonyl compounds (e.g., methylglyoxal [MG] and glyoxal [GO]), formed as intermediate products of the Maillard reaction, irreversibly and progressively modify proteins over time and yield advanced glycation end products (AGEs), which are thought to contribute to the development of diabetes mellitus and its complications. Several studies have shown that higher levels of MG are present in diabetic patients' plasma than in healthy people's plasma. Thus, decreasing the levels of MG and GO will be an effective approach to reduce the formation of AGEs and the development of diabetic complications. Here, we briefly describe our effort in searching for non- or less-toxic trapping agents of reactive dicarbonyl species from dietary sources. In addition, we have discovered that commercial beverages contain extremely high levels of MG. The potential hazardous effects of dietary MG on humans remain to be explored.