The stress purported by the various reactive oxygen species (ROS) which threaten to oxidize biological moieties involved in various organ systems and thus inducing damage is called “Oxidative Stress”. Oxidative stress represents an imbalance between the production of ROS and a biological system’s ability to readily detoxify or repair the resulting damage. This antioxidant defense has two components, for example, enzymes and low-molecular-weight antioxidants component. Various enzymes which serve to scavenge ROS include superoxide dismutase, catalase, glutathione peroxidase and peroxiredoxins. Other antioxidants include α-lipoic acid, mixed carotenoids, coenzyme Q10, bioflavonoids, minerals and vitamins, which work against free radicals. Apart from ageing, oxidative stress is associated with a number of diseases including cancer, cardiovascular diseases (CVD), diabetes, etc. Oxidative stress, when associated with electrocardiographic aspects of coronary artery disease (CAD) indicates an accelerated course of atherosclerosis in the onset phase and an additional thrombogenic risk in the ischemic disease phase; and when associated with chronic cardiac failure, it indicates a progressive form with replacement fibrosis. Persons with or at high risk for CAD should be identified early and aggressively treated with a program that involves lifestyle changes, alterations in dietary intake and pharmacologic therapy. The possible role of combined therapy with antioxidant vitamins C, E and carotene and a diet rich in antioxidants could independently inhibit free radical generation and the development of atherosclerosis.