The level of free radicals, such as the oxidative damage caused in the body, are measured by OS markers (malondialdehyde—MDA, oxysterols, isoprostanes, nucleic acid oxidation products, reduced glutathione/oxidized glutathione ratio—GSH/GSSG, antioxidant enzymes: superoxide dismutase—SOD, catalase—CAT) [68], These markers which highlight the interdependence between OS and T2DM, represent a pathway for the development and initiation of adjuvant therapies with antioxidant properties, effectively contributing to metabolic control and delaying the onset of complications. This evidence concerns the gene CAT and type 2 diabetes mellitus.