Natural antioxidants for the prevention of atherosclerosis.

Hypercholesterolemia, cigarette smoking, hypertension, and obesity are known contributing risk factors for the development of atherosclerotic coronary artery disease (CAD). However, they account for only half of all cases of CAD, and the complete pathologic process underlying atherosclerosis remains unknown. Growing evidence suggests that oxidative modification of low-density lipoprotein (LDL) may be of particular importance in the pathogenesis. Oxidized LDL exhibits proatherogenic effects. Therefore, current research has focused on inhibiting the oxidation of LDL as a means of inhibiting the atherosclerotic process. One such approach is to enhance the endogenous antioxidant defense systems within the LDL particle with lipophilic antioxidants such as alpha-tocopherol and beta-carotene, or by supplementing the aqueous-phase antioxidant capacity with ascorbic acid. Observational data suggest a protective effect of antioxidant supplementation on the incidence of CAD; however, specific doses cannot be recommended since the data are inconclusive.