Role of free Radicals

Cardiovascular Disease

Cardiovascular disease is the single largest cause of mortality in the population. Cardiovascular disease is a global term used for a range of diseases, which include ischemic heart disease (IHD), cerebrovascular disease (CVD), and other related diseases, for example myocardial infarction (MI). Excess free radicals are thought to initiate atheroscelerosis by damaging blood vessel walls. LDL-cholesterol has long been implicated in the development of heart disease and many clinicians report that lowering blood cholesterol is the most effective means of combating heart disease. However, LDL only poses a threat after oxidation by free radicals, as it is reported to migrate across the endothelial membrane into the arterial wall. These oxidized components attract macrophages, which absorb and deposit cholesterol within the cell to form what has been referred to as “foam cells”. These foam cells may initiate the formation of an atherosclerotic lesion, which can result in blockage of blood vessels. Interruption of the blood supply causes severe pain, known as angina pectoris, and may eventually cause death of the cardiac tissue

Several epidemiological studies have shown a reduction in cardiovascular disease in individuals supplemented with antioxidants. The “Nurses, Health Study” was undertaken to asses the effects of vitamin intake on the incidence of coronary heart disease. The dietary habits of 87.245 female nurses were examined and involved an eight year follow up with 552 major cases of coronary heart disease, including 115 fatal and 437 non-fatal cases and 183 cases of ischemic stroke. Results showed that increased intake of vitamin E and ß-carotene reduced the incidence of coronary heart disease.

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