Oxidative Stress and Diet: The Health Implications of Advanced Glycation and Lipid Oxidation End-Products

Dear Colleagues,

Activation of oxygen to reactive oxygen species (ROS) is the primordial process for initiation in foods of oxidized dietary proteins, lipids, and glycation/lipid-oxidation end-products (AGEs/ALEs). Lipid and protein oxidation is one of the major degradative processes responsible for losses in food safety and quality. The oxidation of unsaturated fatty acids and reducing sugars results in significant generation of dietary ALEs and AGEs, which are in part cytotoxic and genotoxic compounds. The gastrointestinal tract is constantly exposed to dietary oxidized food compounds; following digestion, a small proportion of them is absorbed into the lymph or directly into the bloodstream. After ingestion of oxidized fats and proteins, animals and humans have been shown to have increased amounts of lipophilic carbonyl and electrophilic compounds in their blood and urine. Oxidized cholesterol in the diet was found to be a source of oxidized lipoproteins in human serum. Some dietary ALEs/AGEs, which are absorbed from the gut into the circulatory system, appear to act as harmful chemicals that activate an inflammatory response that affects not only the circulatory system but also organs such as the liver, kidney, lung, and the gut itself. We believe that repeated consumption of oxidized fat and proteins as a part of one’s diet poses a chronic threat to human health. High concentrations of dietary antioxidants could prevent lipid oxidation and ALE/AGE generation not only in foods but also in certain gastrointestinal conditions and thereby potentially decrease their absorption from the gut. This could explain the health benefits of diets containing large amounts of dietary antioxidants such as those present in fruits and vegetables or products such as red wine or tea consumed during a meal.

Prof. Dr. Joseph Kanner
Prof. Dr. Ron Kohen
Topic Editors