Grape seed extract is an industrial derivative of grape seeds, extremely rich in antioxidants and oligomeric proanthocyanidin complexes (OPCs).
The extract has been linked to a wide range of possible therapeutic properties including healing wounds and treating conditions such as high cholesterol, atherosclerosis, macular degeneration, poor circulation, nerve damage, as well as preventing cancer.
Although many of these health claims are still not completely backed up by "high quality" studies, strong evidence is beginning to emerge on grape seed extract's extensive health benefits.
Grape seed extract is available as a dietary supplement in either a liquid form, tablets or capsules. Supplements generally contain between 50 to 100 mg of the extract.
This Medical News Today information article provides details on the benefits of grape seed extract as well as side effects and precautions associated with its use.
What are the benefits of grape seed extract
Studies on animal models have revealed that the extract can be effective in treating heart diseases. Some experts think that grape seed extract could even have anticancer and cancer chemopreventive potential.
Over recent years there has been a great deal of research pointing to key therapeutic properties of the grape seed extract. Listed below are some of the key findings.
Health benefits associated with grape seed extract:
- Healing wounds - Grape seed extract can heal dermal wounds.
A study, published in the journal Free Radical Biology and Medicine1, "provided firm evidence to support that topical application of GSPE represents a feasible and productive approach to support dermal wound healing."
- Improving bone strength - Including grape seed extract in your diet with calcium has a "beneficial effect on bone formation and bone strength for the treatment of bone debility caused by a low level of calcium," according to research published in the Journal of Musculoskeletal & Neuronal Interactions.2
- Preventing skin cancer - Grape seeds contain proanthocyanidins which can prevent the development of cancer.
A study, published in the journal Molecular Nutrition & Food Research3, found that grape seeds have properties that can reduce the severity of skin cancer. The researchers concluded that grape seed extracts "could be useful in the attenuation of the adverse UV-induced health effects in human skin."
- Cardiovascular benefits - The antioxidants in grape seed extract can potentially protect the blood vessels from becoming damaged, which may prevent high blood pressure.
According to one study, published in the journal Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis4, "grape seed proanthocyanidin extract (GSPE) provides superior antioxidant efficacy as compared to Vitamins C, E and β-carotene."
- Reducing edema (swelling) - Taking grape seed extract can help reduce the swelling that occurs after an injury or surgery.
A double-blind, placebo-controlled study found that breast cancer patients who took 600 mg of grape seed extract every day for 6 months had less edema compared to those on placebo.
- Preventing cognitive decline - Grape seed extract is very high in proanthocyanidins (oligomers of monomeric polyphenols) which may prevent cognitive decline.
One study identified "a critical role for grape seed proanthocyanidin extract (GSPE) as a neuroprotectant in the hippocampus and in preventing cognitive loss with aging."5
Video - Dr. John Gray talks about the possibility of using grape seed extract to reduce symptoms of ADHD.
Other potential benefits associated with grape seed extract:6
- Treating tooth decay7
- Protecting against pathogens
- Improving night vision
- Alzheimer's disease
- Treating diabetic retinopathy and improving blood sugar control
- Relieving symptoms of chronic venous insufficiency
- Anti-aging properties (protecting collagen and elastin)
Side effects and precautions
Common side effects include:
It is important to talk to your doctor before taking grape seed extract as it can affect the way that certain medications are broken down in the liver.
It is possible that grape seed extract can act as a blood-thinner, which increases the risk of bleeding if taken along with anticoagulants such as warfarin or aspirin. According to RxList8, "Taking grape seed along with warfarin (Coumadin) might increase the chances of bruising and bleeding."
In addition, pregnant women should completely avoid taking grape seed extract supplements.
Written by Joseph Nordqvist
Reviewed by: Megan Ware, RDN, LD, registered dietitian and nutritionist