Grape Seed extract is rich in a particular type of flavonoid (a polyphenol) called Oligomeric Proanthocyanidins (OPCs) and is comprised of dimer polymerizations of catechins. Not only is this powerful antioxidant found highly concentrated in grape seeds, but OPCs are also found in other purple and red-colored plant seeds and skin (i.e. blueberries and cranberries). Though grape seed extract OPCs are not extracted from wine, it is well known that red wine contains high concentration of OPCs and is postulated as the basis of the low cardiovascular disease in France despite the presence of saturated fats in the diet (also known as the French Paradox). Proanthocyanidins (OPCs) exert beneficial effects on circulation and cardiovascular function, while also it has been demonstrated to significantly counter elevated blood pressure.
The impact of grape seed OPCs on cardiovascular function has been studied for decades, however only recently scientists investigated its effects on circulating levels of Paroxonase (PON – a liver enzyme that has been shown to protect against oxidation of cholesterol) and reduce circulating LDL cholesterol. In an 8 week randomized double-blind placebo-controlled clinical trial, scientists examined the effects of administering 200 mg grape seed extract (95% OPC) per day on seventy subjects. The OPC-treated group were observed with significant benefits including reduced Total Cholesterol, reduced LDL Cholesterol, Triglyceride, reduced Triglyceride, and increased Paroxonase levels. A growing body of evidence indicates that Paroxonase is protective against vascular disease. Furthermore, the benefits of reduced triglycerides, total cholesterol, LDL cholesterol show OPCs protective effects against the classic conditions associated with dyslipidemia.
While there is variability in the types of grape seed extract OPCs products, there are multiple human studies showing that the extract significantly lowers blood pressure. A three-arm intervention trial (placebo versus 150 mg versus 300 mg/day of grape seed extract) was conducted to assess the impact of a grape seed OPC extract on 119 pre- and mildly hypertenive subjects. After 16 weeks of administering the OPC supplement, significant (and dose dependent) beneficial effects were demonstrated in the OPC treatment group. 0.05). While the placebo group registered an average blood pressure of 141 mm Hg, the low dose OPC treatment group pressure value was 123 mm Hg, and the high dose OPC treatment group’s blood pressure was an average value of 112 mm Hg. Also, the treatment groups presented reduced diastolic blood pressure as opposed to the placebo. In addition to the blood pressure measurements, laser Doppler tests (conducted to estimate microcirculatory capacity) also showed positive effects for the OPC treatment groups. View research
Grape Seeds are utilized and extracted in a standardized process to concentrate the bioactive compounds known as oligomeric proanthocyanidins (OPCs) to a level of 95%.