Proanthocyanidin (OPC), a powerful antioxidant found in grape seeds, grape skins, strawberries and French maritime pine bark, has anti-inflammatory properties which have been shown to promote normal blood flow and thus benefit the cardiovascular system. In Doctor Myatt's words, OPC's prevent "blood sludge" that can cause strokes and heart attacks. OPC's work like aspirin (only better and safer) to prevent abnormal blood clotting. OPC's may be a superior answer for those who need thinner blood (like people with arrhythmias) as a safer alternative to coumadin. OPC's are also called "pycnogenol" when they are derived from pine bark (the grape seed extract is slightly more potent and less expensive. You will see the terms pycnogenol, OPC's, grape seed extract used interchangeably).

In one study, 38 cigarette smokers were divided into two groups and received either 500 mg of aspirin or 125 mg of Pycnogenol. After taking these doses, each subject smoked a cigarette, which is known to increase blood platelet aggregation (blood clumping). After two hours, blood samples were analyzed. Both groups has greatly reduced platelet aggregation, but those in the aspirin group had increased bleeding times while those in the OPC group did not. Other studies in smokers have also shown the anti-aggregation effect of OPC's.

In another study, 30 people were given Pycnogenol and 10 were given placebo. People in the Pycnogenol group had significant reduction in blood pressure, capillary (small blood vessel) leakage, and blood vessel inflammation, all risk factors for heart disease. There were no negative side effects or adverse changes in blood chemistries from pycnogenol.

Pycnogenol benefits the cardiovascular system by decreasing inflammation and improving blood viscosity in both normal and diabetic subjects. These effects can be especially important to diabetics. New research shows that OPC's have even more benefits for diabetics by helping to lower blood sugar levels and improving microcirculation.

OPC's were administered to diabetic patients. Leg ulcers (which often result in gangrene and loss of limbs in diabetics) healed 25-29% faster in the group taking OPC's. This is a significant benefit for diabetic patients and could help prevent loss of limbs that often occurs in diabetes.

OPC's have also been shown to help lower blood sugar levels. Researchers looked at the effect that Pycnogenol on alpha-glucosidase, an enzyme that breaks down carbohydrates into glucose molecules. In this study, pycnogenol was compared to acarbose, a synthetic drug (sold under the brand name Precose) that inhibits alpha-glucosidase. Pycnogenol was found to be 190 times more potent at inhibiting alpha-glucosidase, producing a greater delay in glucose absorption. At higher concentrations, OPC's greatly slowed the entrance of carbohydrates into the blood stream compared to the drug.

Another study showed that pycnogenol improved the level of microangiopathy (small blood vessel abnormalities) decreased capillary filtration, improved symptoms and reduced edema in 18 out of 18 diabetic patients, with no subjects dropping out of the study due to adverse side effects. There were no improvements seen in the control group.

OPC's have been shown in French trials to help limit the progression of diabetic retinopathy. In one study, 60% of diabetics taking 150 mg per day of OPCs from grape seed extract had no progression of retinopathy compared to 47% of those taking a placebo.

Another trial including 77 subjects with type 2 diabetes, (half receiving 100 mg of Pycnogenol and half received a placebo daily), showed after 12 weeks that subjects in the Pycnogenol group had significantly lowered their plasma glucose levels compared to placebo. Pycnogenol subjects were also found to have improved artery function. In another trial of 30 type 2 diabetics, researchers found that increasing doses of pycnogenol (doses of 50, 100, 200, and 300 mg) lowered blood sugar levels in a dose-dependent fashion. (The more grape seed extract, the lower the blood sugar levels). Subjects who received 100 to 300 mg of Pycnogenol had the most significant lowering of their fasting glucose levels.

Talc (talcum powder) increases "ovarian neoplastic transformation" (turns cells of the female ovary into cancerous cells). A brand new study showed that pycnogenol blocked this talc-induced cancerous change in ovarian cells. PC's have also been shown to induce apoptosis (programmed cell death) in breast cancer cells but not in normal breast tissue.

OPc's reduce four factors know to stimulate cancer cell growth: blood sugar levels, insulin levels, free radical and inflammation. This means that OPC's may be a potent factor not only in cancer prevention but also in cancer treatment. (See our medical paper on cancer diet and nutrition for cancer for full details).

If heart-protective, anti-diabetic, anti-cancer effects aren't enough to make you consider adding grape seed extract to your supplement regimen, here are a few more benefits of this amazing flavonoid for you to consider:

* anti-allergenic (grape seed stabilizes histamine release and so acts as a natural anti-histamine, without any drowsy side-effects). Asthmatic children who took pycnogenol were able to decrease their asthma medications.

* improves skin elasticity by increasing collagen in the skin. For this reason, OPC's are often used in skin rejuvenation programs.

* prevents varicose veins by strengthening blood vessels and increasing collagen (same reason it helps improve aging skin).

* helps prevent Alzheimer's disease by blocking the formation of beta amyloid (a protein associated with Alzheimer's).

* Reduces symptoms of endometriosis. This is JUST IN today in Family Medicine journal, yet another study showing positive benefit.