Grape seed extract has been shown to:
- Help reduce risk of cataracts5
- Provide potent antioxidants67
- Reduce risk of, and even reverse, atherosclerosis8910
- Provide cardiovascular support1112
- Support vascular strength and flexibility131415
- Reduce edema (inflammation and swelling)161718
- Protect against cancer19202122
Grape seed extract (GSE) (Vitis vinnifera) is simply an extract from grape seeds from red grapes. Grape seeds have a high content of compounds known as oligomeric proanthocyanidins—better known as OPCs—which are also found in a variety of fruits and vegetables, including cranberries, blueberries, bilberries, and green and black tea. These naturally occurring antioxidants have been shown to exert a broad spectrum of biological, pharmacological and therapeutic activities against free radicals and oxidative stress.2 Also, OPCs are distinct from other flavonoids because their simple chemical structure allows them to be readily absorbed into the bloodstream.
Most OPC nutritional supplements are made from grape seed extract or the bark of maritime pine (Pycnogenol), although GSE usually contains a total of 92% or 95% OPCs, compared to pine bark extracts which contain 80% to 85%. GSE has emerged as the preferred source of OPCs, which makes sense, especially since the overwhelming majority of the published clinical and experimental studies over the past 20 years have been performed on GSE, not the extract of pine bark.3
The Discovery of OPCs
In 1951, Jacques Masquelier of the University of Bordeaux was inspired to investigate the constituents of pine trees after coming across a story that reads something like this:
In 1532, a French explorer and his crew were trapped by ice in the Saint Lawrence River. A Native American suggested they make tea from the needles and bark of a local pine tree, which saved many of the men from developing scurvy.4
When Masquelier extracted OPCs from the bark of the maritime pine, he found that they could duplicate many of the functions of vitamin C. He named the active components of the pine bark pycnogenols. This term was used to described an entire complex of proanthocyanidin complexes found in a variety of plants including pine bark, grape seed, lemon tree bark, cranberries and citrus peels. Instead of using the term pycnogenols to describe these compounds, the scientific community now uses the terms proanthocyanidins, oligomeric proanthocyanidin complexes (OPCs) and procyanidolic oligomers(PCO).3
Masquelier patented the method of extracting OPCs from pine bark in France in 1951 and from grape seeds in 1970. Extensive research on the OPC extract from grape seeds went on between 1951 and 1971, as well as intensive research from 1972 to 1978. The research in the 1970s was carried out with the goal of getting the approval for grape seed extract to be classified as a medicinal agent in France.
Today, although pine bark extract is still sold in France, sales for the grape seed extract are approximately 400 times higher and it remains the only OPC with the status of a medicinal agent3 —the equivalent of a FDA approval.
Grape seed extract is considered to be a powerful antioxidant that protects the body from premature aging and disease. Research shows that GSE is beneficial in many areas of health, and is even capable of promoting youthful skin, cellular health, elasticity, and flexibility. OPCs also improve blood circulation by strengthening capillaries, arteries, and veins.1
A number of recent scientific studies also demonstrate that grape seed extract OPCs reduce the risk of cancer, cardiovascular disease and a number of the chronic diseases associated with aging. Although most of the studies conducted on GSE have been done in vitro (cell cultures tested in a test tube) and on animals, more studies are being done on humans, and the results are extremely promising.
GSE offers potent antioxidant support
A study at the University of Milan, Italy evaluated the effect that grape seed extract supplementation had on oxidative stress markers in 10 healthy volunteers.
The volunteers received a daily dose of 110 mg of OPCs for 30 days. Fasting blood samples were taken before and at the end of the supplementation period, and then again after 7 days of not having taken the supplements. The results showed that the OPCs provided antioxidant protection by increasing levels of alpha tocopherol (liposoluble vitamin E) in red blood cells, and by reducing DNA oxidative damage.6
A study at the Government College of Pharmacy in Bangalore, India found that grape seed extract produced the most optimal antioxidant activity in laboratory rodents. The animals were first treated with a substance that decreased the natural antioxidants catalase, superoxide dismutase (SOD), and peroxidase by 81, 49, and 89% respectively. On the other hand, lipid peroxidation—the break down of fats in the arteries and veins due to free radical attack, and the main cause of artherosclerosis in humans—increased nearly threefold.
Compared to the control group, the catalase, SOD, and peroxidase levels were restored by 43.6, 73.2, and 54%, respectively, in the rodents that were pretreated with GSE, whereas lipid peroxidation was restored to values comparable with the control.7
This study indicates that GSE has the potential to offer potent antioxidant support and help control lipid peroxidation, both key factors in heart health, as we see below.
Grape OPCs reduce atherosclerosis risk and heart disease
A large body of evidence shows that oxidized low-density lipoprotein (LDL – “bad” cholesterol) plays a major role in atherosclerosis and heart disease. If this oxidative stress is not neutralized, it causes plaque to form in the walls of the arteries in the heart. OPCs, however, protect against free radicals and oxidative stress.
A French in-vitro study examined the effects of OPCs in grape seed extract compared with whole grape and grape skin extracts. The GSE was the most effective at preventing LDL oxidation.8
Scientists around the world are realizing the value of GSE in reducing LDL oxidation associated with heart disease. Roger Corder, a scientist from the William Harvey Research Institute, Queen Mary, University of London gave a presentation to the American Heart Association meeting in Chicago in November 2002, which outlined how procyanidins found in grape seeds and grape skin appear to stall the development of atherosclerosis.
The team of scientists at the William Harvey Research Institute mainly focused their research on vascular endothelium, the flat endothelial cells which line all blood vessels in a single layer and which have numerous functions.
They established that red wine and grape seed extract appear to inhibit the production of endothelin-1, a protein that has long been incriminated in the formation of the early signs of artery disease. Previous studies have shown that suppression of ET-1 can reduce the risk of a heart attack in those with heart disease. The news is significant because it indicates polyphenols may be beneficial for more than just their antioxidant properties.910
May reduce risk of heart attack
Researchers at the University of Connecticut School of Medicine concluded that animals fed with grape seed OPCs were resistant to heart attack (myocardial infarction). This was demonstrated by the way in which the heart muscle contracted after blood flow was restricted. Grape seed extract was given to the animals before they received a compound that restricted blood flow. The OPCs were found to exert a cardioprotective effect against the restricted blood flow, which the researchers attributed to grape seed’s ability to directly scavenge peroxyl and hydroxyl radicals, and to reduce oxidative stress developed during ischemia (restricted blood flow).11
Helps protect smokers from oxidative stress
Grape seed extract has been shown to protect low-density lipoproteins (LDL) under oxidative stress in heavy smokers. A fourteen-week clinical study involved 24 healthy smokers over the age of 50 who smoked more than 10 cigarettes per day. During the first four-week stage, one group was given 150 mg/d of a GSE supplement and the other was given 150 mg/d of placebo. The fatty component of the blood was measured before and after the end of each phase. “Treatment with the supplement, compared with the placebo, induced a 20-percent reduction of the lipidic peroxidation, with a significant 15-percent increase of LDL resistance to oxidating stress,” explained Roberto Maffei Facino, a professor at Milan University.12 In other words, the GSE supplementation lowered the smokers’ risk for developing heart disease.
Strengthens capillary walls and reduces varicose veins
Grape seed OPCs help stabilize blood vessel walls, reduce inflammation, and generally support tissues containing collagen and elastin—proteins found in cartilage, tendons, blood vessels, skin, and muscle. OPCs have also been shown to strengthen capillaries in double-blind research using as little as 100 mg per day.13
A French double-blind study of 50 women with chronic venous insufficiency (a condition where blood pools in the veins of the lower legs and can result in varicose veins) found that GSE quickly and effectively resolved their symptoms using 150 mg per day.14
Another French double-blind study of 92 patients found that GSE, compared to placebo, significantly reduced peripheral venous insufficiency symptoms, such as edema, pain and cramps. And supplementation with 100 mg taken three times per day, resulted in benefits within four weeks.15
Reduces post-op swelling
Possibly because of their effects on blood vessels, grape seed OPCs can be useful for swelling following an injury or surgery. In double-blind research, they have been reported to reduce the duration of edema after face-lift surgery from 15.8 to 11.4 days.16
Also, a double-blind controlled study found that postoperative breast cancer patients who took 600 milligrams of GSE daily for six months experienced a significant reduction in swelling, pain, and sensations known as paresthesias.17 Another double-blind controlled study found that GSE improved the rate at which swelling disappeared following sports injuries.18
Inhibits growth of cancer cells
Some of the latest research being done on grape seed extract has indicated that it is a chemopreventative, protecting against the proliferation of cancer cells.
A study recently published in June, 2004, discussed GSE’s positive effect on cancer cells in the human intestinal tract.19
Several recent studies at the University of Colorado Health Sciences Center in Denver, have also shown that GSE inhibits the growth of human breast cancer,20 prostate cancer,21 and cancer in endothelial cells.22
How safe is grape seed extract?
Free radicals have been implicated in a myriad of modern day diseases and conditions, including aging, arthritis, atherosclerosis, ischemia, Alzheimer and Parkinson’s disease, AIDS and cancer.
A large number of synthetic and natural antioxidants have been demonstrated to produce beneficial effects on human health and disease prevention. However, the bioavailability and effectiveness of the various antioxidants are unique to each antioxidant, and some are more effective than others.
As we have seen, grape seed extract’s OPCs possess a broad spectrum of biological, pharmacological and therapeutic activities against free radicals and oxidative stress. Scientists have demonstrated that GSE is highly bioavailable and even provides significantly greater protection against free radicals and free radical-induced lipid peroxidation and DNA damage than vitamins C, E and beta-carotene.25
While vitamins C, E and beta-carotene are certainly potent antioxidants and necessary for overall health, if you want extra protection against heart disease and cancer, and added support for healthy circulation and eye health, consider taking grape seed extract for added support and peace of mind.
- Shi J, Yu J, Pohorly JE, Kakuda Y. Polyphenolics in grape seeds-biochemistry and functionality. J Med Food. 2003 Winter;6(4):291-9.
- Bagchi D, Bagchi M, Stohs SJ, Das DK, Ray SD, Kuszynski CA, Joshi SS, Pruess HG. Free radicals and grape seed proanthocyanidin extract: importance in human health and disease prevention.Toxicology. 2000 Aug 7;148(2-3):187-97.
- Murray, Michael T. “PCO Sources: Grape Seed vs Pine Bark.” The Healing Power of Herbs. Prima Publishing, Rocklin, CA. 1995.
- Murray M, Pizzorno J. Procyanidolic oligomers. In: Murray M, Pizzorno J, eds. The Textbook of Natural Medicine. 2nd ed. London: Churchill Livingston; 1999:899-902.
- Yamakoshi J, Saito M, Kataoka S, Tokutake S. Procyanidin-rich extract from grape seeds prevents cataract formation in hereditary cataractous (ICR/f) rats. J Agric Food Chem. 2002 Aug 14;50(17):4983-8.
- Simonetti P, Ciappellano S, Gardana C, Bramati L, Pietta P. Procyanidins from Vitis vinifera seeds: in vivo effects on oxidative stress. J Agric Food Chem. 2002 Oct 9;50(21):6217-21.
- Chidambara Murthy KN, Singh RP, Jayaprakasha GK. Antioxidant activities of grape (Vitis vinifera) pomace extracts. J Agric Food Chem. 2002 Oct 9;50(21):5909-14.
- Shafiee M, Carbonneau MA, Urban N, Descomps B, Leger CL. Grape and grape seed extract capacities at protecting LDL against oxidation generated by Cu2+, AAPH or SIN-1 and at decreasing superoxide THP-1 cell production. A comparison to other extracts or compounds. Free Radic Res. 2003 May;37(5):573-84.
- Hagen, Pat. “Fresh Heart for Red Wine Drinkers” The Scientisthttp://www.biomedcentral.com/news/20011231/02
- Institute of Food Technologists.
- Sato M, Maulik G, Ray PS, Bagchi D, Das DK. Cardioprotective effects of grape seed proanthocyanidin against ischemic reperfusion injury. J Mol Cell Cardiol. 1999 Jun;31(6):1289-97.
- Vigna GB et al. “Effect of a standardized grape seed extract on low-density lipoprotein susceptibility to oxidation in heavy smokers.”Metabolism. 52, 10:1250-7, 2003. (http://www.ncbi.nih.gov)
- Dartenuc JY, Marache P, Choussat H. Resistance Capillaire en Geriatrie Etude d’un Microangioprotecteur. Bordeaux Médical1980;13:903-7 [in French].
- Delacroix P. Etude en Double Avengle de l’Endotelon dans l’Insuffisance Veineuse Chronique. Therapeutique, la Revue de Medicine 1981;27-28 Sept:1793-802 [in French].
- Thebaut JF, Thebaut P, Vin F. Study of Endotelon in functional manifestations of peripheral venous insufficiency. Gazette Medicale1985;92:96-100 [in French].
- Baroch J. Effect of Endotelon in postoperative edema. Results of a double-blind study versus placebo in 32 female patients. Ann Chir Polast Esthet 1984;29:393-5 [in French].
- Pecking A, Desprez-Curely JP, Megret G. Oligomeric grape flavanols (Endotelon®) in the treatment of secondary upper limb lymphedemas [translated from French]. [Source unknown]. 1989:69-73.
- Parienti J-J, Parienti-Amsellem J. Post-traumatic edemas in sports: a controlled test of Endotelon® [translated from French]. Gaz Med Fr.1983;90:231-236.
- Laurent C, Besancon P, Auger C, Rouanet JM, Caporiccio B. Grape seed extract affects proliferation and differentiation of human intestinal Caco-2 cells. J Agric Food Chem. 2004 Jun 2;52(11):3301-8.
- Sharma G, Tyagi AK, Singh RP, Chan DC, Agarwal R. Synergistic anti-cancer effects of grape seed extract and conventional cytotoxic agent doxorubicin against human breast carcinoma cells. Breast Cancer Res Treat. 2004 May;85(1):1-12.
- Singh RP, Tyagi AK, Dhanalakshmi S, Agarwal R, Agarwal C. Grape seed extract inhibits advanced human prostate tumor growth and angiogenesis and upregulates insulin-like growth factor binding protein-3. Int J Cancer. 2004 Feb 20;108(5):733-40.
- Agarwal C, Singh RP, Dhanalakshmi S, Agarwal R. Anti-angiogenic efficacy of grape seed extract in endothelial cells. Oncol Rep. 2004 Mar;11(3):681-5.
- Wren AF, Cleary M, Frantz C, Melton S, Norris L. 90-day oral toxicity study of a grape seed extract (IH636) in rats. J Agric Food Chem. 2002 Mar 27;50(7):2180-92.
- Yamakoshi J, Saito M, Kataoka S, Kikuchi M. Safety evaluation of proanthocyanidin-rich extract from grape seeds. Food Chem Toxicol. 2002 May;40(5):599-607.
- Bagchi D, et al. Free radicals and grape seed proanthocyanidin extract: importance in human health and disease prevention.Toxicology. 2000 Aug 7;148(2-3):187-97.