Establishing the significance and optimal intake of dietary antioxidants: The biomarker concept

Diets rich in fruits and vegetables are associated with decreased risk of c ardiovascular disease and cancer: Biomarkers of oxidative DNA damage and li pid peroxidation can be used to establish the role of antioxidants in this protection and the optimal intake of those antioxidants. This concept is ba sed on the presumptions that oxidative DNA damage is a significant contribu tor to the age-related development of some cancers and that lipid peroxidat ion plays a key role in the development of cardiovascular disease. Mass spe ctrometric measurements of various families of isoprostanes (F-2-, F-3-, an d F-4-isoprostanes) and of multiple DNA base oxidation products are probabl y the most promising biomarkers for use in human nutritional intervention s tudies. Biomarker studies should precede, as well as accompany, major inter vention trials that measure disease incidence. The use of biomarkers provid es a logical scientific basis for major intervention trials of antioxidants ; such trials will, in turn, eventually validate or disprove the biomarker concept.