The latest issue of Molecular Nutrition & Food Research plays host to a debate on advanced glycation endproducts (AGE), their receptors (RAGE) and advanced lipoxidation end-products (ALEs). The latter are oxidized lipids suspected as a mechanism by which reactive oxygen species wreck havoc throughout the body - the free radical theory of aging.
It is rather interesting to see the biogerontological viewpoint - AGEs are one root cause of aging, or at the very least a range of age-related disease - presented in debate with the nutritionist's viewpoint of "we eat these things in volume with no ill effects, so of course they're safe." I massively oversimplify both sides in that statement of course, but the nutritionist's view might be equated with the view of aging and age-related degeneration as "normal." In any case, a representative sample of the papers on offer:
Thermal processing of food results in the formation of various novel compounds, among others advanced glycation endproducts (AGEs). AGEs result from nonenzymatic glycation reactions between reducing sugars and free amino groups of proteins, peptides, or amino acids. Due to their potential noxious effects, alimentary AGEs are also called glycotoxins. This review provides a summary of the available evidence on the health effects of exaggerated intake of thermally treated food. Data from experimental studies in rodents and from clinical studies in healthy volunteers and in patients suffering from selected diseases in which AGEs are of pathogenetic importance (diabetes, chronic renal failure) are summarized. It is concluded that, an exaggerated intake of thermally processed foods may exert in vivo diabetogenic and nephrotoxic effects, induce low-grade inflammation, enhance oxidative stress, and promote atherosclerosis.
Food intake is only one source of AGEs, however - and it may not be the most important one for people following a sane diet. Your own metabolism cheerfully churns out AGEs of many different varieties. Over the years, those that cannot be effectively broken down will damage and hinder your biochemistry ever more seriously. Progress towards AGE-breaker drugs - and other technologies like bioremediation - capable of safely removing these damaging compounds is one important facet of longevity science.