Melanoidins from coffee and lipid peroxidation

Dietary lipid oxidation products are thought to be an important risk factor in the development of cardiovascular diseases. Lipid oxidation products may be already present in oxidized food and they may be generated during digestion of highly oxidizable food such as meat. In vitro and in vivo studies are consistent for a role of coffee high molecular weight melanoidins in the prevention of oxidative damage. Since coffee melanoidins are poorly bioavailable, the gastro-intestinal tract itself might constitute their main biological site of action where they reach high concentrations following coffee consumption. In the stomach they inhibit the peroxidation of meat lipids, decreasing the synthesis of hydroperoxides and secondary lipoxidation products. The reduction in the formation of these pro-atherogenic compounds has been shown to be followed by a decrease in their absorption in the human volunteers. The ability of coffee melanoidins to inhibit lipid peroxidation may contribute to their health benefits, since dietary oxidized lipid and advanced lipid oxidation endproducts are involved in the development of atherosclerosis and other diseases.