Grape Seed Extract

Plant Part Used



The flavonoid-rich active compound in grape seed is claimed to be one of the most important natural products to be discovered in the last several years. These flavonoids are currently being touted as some of the most potent free radical scavengers. By some estimates, they are more powerful than vitamin E and vitamin C. Additionally, flavonoids enhance absorption of and work in concert with vitamin C.

Interactions and Depletions


Dosage Info

Dosage Range

25-100mg (standardized extract), 1-3 times a day.

Most Common Dosage

50mg (standardized extract), 2 times a day.


[span class=doc]Standardization represents the complete body of information and controls that serve to enhance the batch to batch consistency of a botanical product, including but not limited to the presence of a marker compound at a defined level or within a defined range.[/span]

The most current available medical and scientific literature indicates that the dietary supplement should be standardized to a procyanidolic value of greater than 95% or at least 80% proanthocyanidins or 95% polyphenols per dose.

Reported Uses

Applications for grape seed extract center on its role as a powerful antioxidant. Studies suggest that the active components of grape seed inhibit the destruction of collagen structures. (1) This support of collagen structures leads to greater overall health of the tiny capillaries that supply energy to the body’s tissues. (2) , (3) Studies involving people with various circulation problems in their extremities have benefited from grape seed extract. These studies have indicated that a majority of the people taking the grape seed extract compared to those taking placebo had either an improvement in their condition, a decrease in their symptoms or both. (4) , (5) , (6)

In addition, the active compounds in grape seed scavenge many types of harmful free-radicals that can damage cell membranes while supporting healthy blood flow. (7) , (8) , (9) Grape seed extract may also have the ability to block platelet activating factor (PAF), thus lengthening the time it takes for the blood to form clots. This effect is comparable to that of aspirin and its effect on the ability of the blood to form clots. (10)

Other studies have found that grape seed may inhibit the release of elements that cause inflammation. (11) , (12) This function has also proven useful in the treatment of some allergies, although some studies have not demonstrated any benefit when grape seed extract is used for seasonal allergies. (13)

The active components of grape seed extract, proanthocyanidins, may also be of benefit in individuals with vision disorders such as glaucoma, diabetic retinopathy, macular degeneration, vitreous degeneration and corneal stroma ulceration. (14) , (15) , (16) Recent medical research has indicated that the proanthocyanidins may not only protect the body against the damaging effects of radiation therapy (17) and certain types of chemotherapy, (18) but they may also be damaging to certain cancer cells including very specific types of human breast cancer cells, lung cancer cells and stomach cancers. (19)

Toxicities & Precautions


[span class=alert]Be sure to tell your pharmacist, doctor, or other health care providers about any dietary supplements you are taking. There may be a potential for interactions or side effects.[/span]


This dietary supplement is considered safe when used in accordance with proper dosing guidelines. (20)

If you are planning to have any type of surgery or dental work, stop using this dietary supplement for at least 14 days prior to the procedure.

Health Conditions

If you have a bleeding disorder talk to your doctor before taking this dietary supplement.

Pregnancy/ Breast Feeding

To date, the medical literature has not reported any adverse effects related to fetal development during pregnancy or to infants who are breast-fed. Yet little is known about the use of this dietary supplement while pregnant or breast-feeding. Therefore, it is recommended that you inform your healthcare practitioner of any dietary supplements you are using while pregnant or breast-feeding.

Age Limitations

To date, the medical literature has not reported any adverse effects specifically related to the use of this dietary supplement in children. Since young children may have undiagnosed allergies or medical conditions, this dietary supplement should not be used in children under 10 years of age unless recommended by a physician.


  1. View Abstract: Bagchi D, et al. Oxygen Free Radical Scavenging Abilities of Vitamins C and E, and a Grape Seed Proanthocyanidin Extract in Vitro. Res Commun Mol Pathol Pharmacol. 1997;95(2):179-89.
  2. View Abstract: Fauconneau B, et al. Comparative Study of Radical Scavenger and Antioxidant Properties of Phenolic Compounds from Vitis vinifera Cell Cultures Using in Vitro Tests. Life Sci. 1997;61(21):103-10.
  3. View Abstract: Frankel EN, et al. Inhibition of Oxidation of Human Low-density Lipoprotein by Phenolic Substances in Red Wine. Lancet. 1993;341(8843):454-57.
  4. Thebaut JF, Thebaut P, Vin F. Study of Endotelon in Functional Manifestations of Peripheral Venous Insufficiency. Gaz Med France. 1985;92:96-100.
  5. View Abstract: Royer RJ, Schmidt CL. Evaluation of Venotropic Drugs by Venous Gas Plethsymograhy. A Study of Proanthocyanidolic Oligomers. Sem Hop. 1981;l57:2009-2013.
  6. Dartenuc JY, Marache P, Choussat H. Capillary Resistance in Geriatry. A Study of a Microangioprotector – Endotelon. Bord Med. 1980;13:903-907.
  7. View Abstract: Robert L, et al. The Effect of Procyanidolic Oligomers on Vascular Permeability. A Study Using Quantitative Morphology. Pathol Biol. (Paris). 1990;38(6):608-16.
  8. View Abstract: Zafirov D, et al. Antiexudative and Capillaritonic Effects of Procyanidines Isolated from Grape Seeds (V. vinifera). Acta Physiol Pharmacol Bulg. 1990;16(3):50-54.
  9. View Abstract: Chang WC, et al. Inhibition of Platelet Aggregation and Arachidonate Metabolism in Platelets by Procyanidins. Prostaglandins Leukot Essent Fatty Acids. Dec1989;38(3):181-88.
  10. View Abstract: Chang WC, et al. Inhibition of Platelet Aggregation and Arachidonate Metabolism in Platelets by Procyanidins. Prostaglandins Leukot Essent Fatty Acids. Dec1989;38(3):181-88.
  11. View Abstract: Maffei Facino R, et al. Procyanidines from Vitis vinifera Seeds Protect Rabbit Heart from Ischemia/Reperfusion Injury: Antioxidant Intervention and/or Iron and Copper Sequestering Ability. Planta Med. 1996;62(6):495-502.
  12. View Abstract: Maffei Facino R, et al. Free Radicals Scavenging Action and Anti-enzyme Activities of Procyanidines from Vitis vinifera. A Mechanism for Their Capillary Protective Action. Arzneim-Forsch/Drug Res. 1994;44(5):592-601.
  13. View Abstract: Bernstein CK, Deng C, Shuklah R, et al. Abstract 1018 Double Blind Placebo Controlled (DBPC) Study of Grapeseed Extract in the Treatment of Seasonal Allergic Rhinitis (SAR). American Academy of Allergy, Asthma and Immunology (AAAAI) 57th Annual Meeting. Mar2001.
  14. View Abstract: Huang SH, Adamis AP, Wiederchain DG, et al. Matrix Metalloproteinases and Their Inhibitors in Aqueous Humor. Exp Eye Res. May1996;62(5):481-90.
  15. Verin MMP, Vilda A, Maurin JF. Therapeutic Essay. Retinopathy and OPC. Bord Med. 1978;11:1467-1473.
  16. View Abstract: Barracchini A, Franceschini N, Filippello M, et al. Leukocyanidines and Collagenases: In Vitro Enzyme Inhibition Activity. Clin Ter. Jul1999;150(4):275-8.
  17. View Abstract: Castillo J, Benavente-Garcia O, Lorente J, et al. Antioxidant Activity and Radioprotective Effects Against Chromosomal Damage Induced In Vivo by X-rays of Flavan-3-ols (Procyanidins) from Grape Seeds (Vitis vinifera): Comparative Study Versus Other Phenolic and Organic Compounds. J Agric Food Chem. May2000;48(5):1738-45.
  18. View Abstract: Joshi SS, Kuszynski CA, Bagchi M, et al. Chemopreventive Effects of Grape Seed Proanthocyanidin Extract on Chang Liver Cells. Toxicology. Nov2000;155(1-3):83-90.
  19. View Abstract: Ye X, Krohn RL, Liu W, et al. The Cytotoxic Effects of a Novel IH636 Grape Seed Proanthocyanidin Extract on Cultured Human Cancer Cells. Mol Cell Biochem. Jun1999;196(1-2):99-108.
  20. View Abstract: Boss PK, et al. Expression of Anthocyanin Biosynthesis Pathway Genes in Red and White Grapes. Plant Mol Biol. 1996;32(3):565-69.






in this scope
Malaysian Herbal Monograph​
Medicinal Herbs & Plants Monographs​
Traditional Chinese Medicine Herbs (Professional Data)
Herbal Medicines Compendium (HMC) - U.S​