100 mg - Standardized Extract Vascular Health Healthy Immune Response NOW Grape Seed Extract is a highly concentrated extract with a minimum of 90% Polyphenols, including Oligomeric Proanthocyanidins (OPCs), which are the potent water-soluble free radical scavenging compounds found in Grape Seeds. A growing body of research indicates that Grape Seed OPCs may help to support the health of vascular, bone, kidney, brain and other tissues by supporting a healthy immune response to normal oxidative and metabolic stress. Vitamin C has been added for its antioxidant power.