Grape Seed Extract contains oligomeric proanthocyanidins (OPCs).* They are flavonoid-rich compounds with very potent antioxidant properties.* OPCs have been found to inhibit lipid peroxidation, and to effect enzyme systems including phospholipase A2, xanthine oxidase, cycloxygenase, and lipoxygenase.* OPCs help maintain capillary strength and integrity and venous tone.*