Grape is a climbing shrub indigenous to Europe and Northern region of Asia. It is now cultivated in warm and tropical areas as well. The extract from the grape seed contains
main active ingredient of proanthocyanidins (OPCs). OPCs effectively protect collagen matrix of connective tissue, protect against free radical damage, and inhibit collagen damage caused by inflammation and infection. OPCs protect against free-radical damage, suggested to be a major cause of the ageing process. The antioxidant effect is 50 times greater than that of vitamin C and E. OPCs appear to improve blood circulation through collagen support. OPCs significantly improved visual performance in dark and after glare tests, improved symptoms in patients with diabetic retinopathies, maculopathies, and other visual dysfunctions, protect fat and cholesterol from oxidation, thus reducing arterial damage leading to heart disease. OPCs stimulate nitric oxide production male penile erection. OPCs help maintain neurotransmitters functioning longer and improve the micro-circulation in the brain. These positive results are due to the effects of increased neurotransmitter lifespan, NO production, and improved brain microcirculation. Most of the published clinical data over 20 years has been on grape seed Grape seed may be more potent than pine bark as only grape seed contains the potent gallic esters of the OPCs, the most active free radical fighting OPCs.