Oligomeric proanthocyanidins (OPCs) are comprised of two, three, or more flavonoid molecules attached to each other. OPCs have strong free-radical scavenging (antioxidant) ability, resulting in inhibition of oxidative damage and protection of blood vessels and other tissues.* OPCs have been shown to protect vascular endothelial cells from oxidative damage and appear to strengthen the resistance of cell membranes to injury and degradation.* They also bind copper and iron, thereby reducing their oxidative effects.* A clinical study of 10 healthy volunteers examining the effect of OPC supplementation on markers of oxidative stress showed significantly increased levels of alpha-tocopherol in red blood cell membranes.*

The primary ingredient in O.P.C.-100, Leucoselect Phytosome, markedly elevates blood total antioxidant capacity.* In a randomized human trial, young healthy volunteers received Leucoselect Phytosome (containing 300 mg of Leucoselect daily) or a placebo. The blood Total Radical-trapping Antioxidant Parameter (TRAP – a measure of antioxidant activity) was measured at several time-points during day one and day five. Within 30 minutes after administration on day one, blood TRAP levels were significantly elevated compared to placebo.* Other studies on Leucoselect Phytosome supplementation have demonstrated a reduction in the oxidation of LDL cholesterol in heavy smokers, reduced oxidative stress in diabetics, and a reduction in oxidative stress after a fatty meal.*

Evidence suggests OPCs stabilize collagen cross-linkage within skin and other connective tissues.* OPCs have also been shown to decrease capillary permeability (thus decreasing bruising).* Clinical studies demonstrate reduced swelling and improved resolution of sports injuries in athletes given OPCs prior to a sporting event.*