The medicinal and nutritional value of grapes (Vitis vinifera) has been heralded for thousands of years. Egyptians consumed this fruit at least 6,000 years ago, and several ancient Greek philosophers praised the healing power of grapes -- usually in the form of wine. European folk healers developed an ointment from the sap of grapevines to cure skin and eye diseases. Grape leaves were used to stop bleeding, inflammation, and pain, such as the kind brought on by hemorrhoids. Unripe grapes were used to treat sore throats and dried grapes (raisins) were used to heal consumption, constipation, and thirst. The round, ripe, sweet grapes, were used to treat a range of health problems including cancer, cholera, smallpox, nausea, eye infections, and skin, kidney, and liver diseases.

Seedless varieties were developed to appeal to fickle consumers, but researchers are now discovering that most of the healthful properties of grapes may actually come from the seeds themselves.

Among other beneficial effects, the active compounds in grape seed are believed to have antioxidant properties. In fact, a recent study of healthy volunteers found that supplementation with grape seed extract substantially increased levels of antioxidants in the blood. Antioxidants are substances that scavenge free radicals -- damaging compounds in the body that alter cell membranes, tamper with DNA (genetic material), and even cause cell death. Free radicals occur naturally in the body, but environmental toxins (including ultraviolet light, radiation, cigarette smoke, and air pollution) can also increase the number of these damaging particles. Free radicals are believed to contribute to the aging process as well as the development of a number of health problems including heart disease and cancer. Antioxidants found in grape seeds can neutralize free radicals and may reduce or even help prevent some of the damage they cause.

Today, professional herbalists use standardized extracts of grape seed to treat a range of health problems related to free radical damage, including heart disease and cancer. Studies in laboratories, animals, and people lend some support to these uses.

Heart disease: Flavonoids found in red wine have been shown to inhibit the oxidation of LDL ("bad") cholesterol. (LDL oxidation can lead to hardening of the arteries or atherosclerosis). Studies have demonstrated a relationship between flavonoid intake (from food) and reduced risk of death from coronary heart disease.

The Mediterranean Style Diet is comprised of whole grains, fresh fruits and vegetables, fish, olive oil, and moderate, daily wine consumption. In a long-term study of 423 patients who suffered a heart attack, those who followed a Mediterranean Style Diet had a 50% to 70% lower risk of recurrent heart disease compared with controls who received no special dietary counseling. Some researchers believe that some of the beneficial effects of the Mediterranean Style Diet are due to flavonoids found in red wine. (Another well-known theory along these lines is called "The French Paradox." The belief is that drinking wine protects those living in France from developing heart disease at as high a rate as those living in the U.S., despite the rich fatty foods they eat.)

Others speculate that the healthful effects of moderate wine consumption are due to its alcohol content and not its flavonoid content. If it is indeed the flavonoids contributing to heart protection, then grape seed extracts offer an important alternative to alcohol, particularly given the down sides of drinking alcohol (see below). A third concept is being proposed by a group of researchers who believe that the beneficial effects of wine may be triggered by a complex interaction of alcohol and flavonoids. As the controversy of which ingredient in wine is the most important continues, both grape seed extracts and red wine continue to be promoted for heart health. Plus, several test tube and animal studies confirm that antioxidants from grapes offer cardioprotection in their own right.

It is also important to note that the use of alcohol is not advocated by the American Heart Association and other organizations because of the potential for addiction and the other serious repercussions such as motor vehicle accidents and the development of hypertension, liver disease, breast cancer, and weight gain. If red wine is consumed, it is recommended that men have no more than 2 glasses (20 g ethanol) per day and women, no more than 1 glass (15 g ethanol).

High cholesterol
In a recent study, 40 people with high cholesterol were randomly assigned to receive grape seed extract, chromium, a combination of both, or placebo for 2 months. The combination of grape seed extract and chromium was more effective than either substance alone or placebo in reducing total and LDL ("bad") cholesterol.

High blood pressure
In one animal study, a proprietary grape seed extract substantially reduced systolic blood pressure in healthy mice. Further studies are needed to determine whether grape seed extract confers the same benefits to people with high blood pressure.

Pancreatitis
In one recent study of only three patients with chronic pancreatitis (inflammation of the pancreas), a commercially available grape seed extract significantly reduced the frequency and intensity of abdominal pain after conventional medications failed to improve symptoms. Further studies are needed to confirm these preliminary findings.

Cancer
Laboratory studies have found that grape seed extract prevents the growth of breast, stomach, and lung cancer cells in test tubes. Grape seed extract was also effective in preventing damage to human liver cells caused by chemotherapy medications. While surveys indicate that many people with cancer are using grape seed extracts, it is still premature to know whether the positive effects seen in the laboratory will prove beneficial for people.

Cellulite
Although herbal extracts have been promoted as anti-cellulite agents, a recent study found that a proprietary herbal product containing grape seed oil, evening primrose oil, ginkgo, sweet clover, sea-weed, and lecithin was no more effective than placebo in getting rid of cellulite.

Other
Professional herbalists may also recommend grape seed extract for a variety of circulatory ailments (including varicose veins and chronic venous insufficiency) and other diseases related to free radical damage, including age-related macular degeneration, an eye disorder that develops with age and can lead to blindness. Grape seed extract may help improve night vision and photophobia (sensitivity to light) as well. Interestingly, some laboratory and animal studies suggest that procyanidins from grape seed may promote hair growth; this idea has yet to be tested in people.

Grapes are native to Asia near the Caspian Sea, but were brought to North America and Europe around the 1600's. This plant's climbing vine has large, jagged leaves, and its stem bark tends to peel. The grapes may be green, red, or purple.

Vitamin E, flavonoids, linoleic acid, and compounds called procyanidins (also known as condensed tannins, pycnogenols, and oligomeric proanthocyanidins or OPCs) are highly concentrated in grape seeds. These healthful compounds can also be found in lower concentrations in the skin of the grape. Procyanidins are also found in grape juice and wine, but in lower concentrations.

Grape seed is available in capsules, tablets, and fluid extracts. Look for products that are standardized to 95% OPC content.

Pediatric

There are no known scientific reports on the pediatric use of grape seed. Therefore, grape seed extracts and supplements are not currently recommended for children. Of course, whole grapes make a healthy snack and are certainly safe for children to consume.

Adult

To prevent heart disease or circulatory disorders, take 50 mg standardized extract (standardized to 95% OPC content) per day. For specific illnesses, 150 to 300 mg per day may be recommended by a qualified healthcare practitioner.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

At the recommended dosage, grape seed is considered very safe. However, pregnant or breastfeeding women should avoid grape seed supplements.

There are no known scientific reports of interactions between grape seed and conventional medications.

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