Grapes have a long history of medicinal purposes, stretching back as far as ancient Greece. Often, this traditional “medicine” came in the form of wine, but its leaves, vines, and fruit were all used to treat concerns ranging from sore throats to cholera to eye infections to nausea. Such remedies were made out of nearly every part of the grape — even the seeds.
Grape seed extract is made from the crushed seeds of wine grapes. Some other names for it include:
- Vitis vinifera
- Oligomeric proanthocyanidins
Grape seed extract is commonly available as an oral capsule or an aromatic oil.
While more research is needed, some preliminary studies suggest that grape seed extract may provide a number of health benefits, including:
Reduction of Swelling
The proanthocyanidins in grape seed extract are a type of flavonoid naturally found in plants. This component of grape seed oil can reduce the amount of leg swelling you would normally experience during long periods of sitting.
Lower Blood Pressure
Researchers who studied the blood pressure of 24 adults with metabolic syndrome — most of whom had prehypertension, or elevated blood pressure levels — found that blood pressure dropped for those who took grape seed extract.
The tannins in grape seed extract are active antioxidants. Because of this, taking grape seed extract may protect the lining of blood vessels from damage. In this way, grape seed extract may have a positive effect on people with heart disease and other issues with circulation.
A promising study showed that this combination was more effective than grape seed oil without chromium, but more research is needed to be sure of this possible cholesterol-lowering effect.
Proponents of grape seed extract have claimed it can decrease your body's production of histamines, which are part of a chain reaction your immune system launches when attacked. Histamines are what cause pesky allergy symptoms such as a runny nose, sore throat, or itchy eyes. However, although researchers have studied this, results are either too limited or too inconclusive to confirm this for sure.
Although early research has suggested that grape seed extract may provide numerous health benefits, experts agree that more research is needed to confirm this. This same lack of thorough research means researchers don’t have a full sense of potential health risks of using grape seed extract, either.
You should speak to your doctor before using grape seed extract if you are:
Pregnant or Breastfeeding
If you are pregnant or breastfeeding, you should avoid using grape seed extract. Its effects on this population have not been sufficiently studied.
Grape seed oil is known to reduce your body's ability to absorb iron, so people with an iron deficiency should be wary of using it.
Taking Blood Thinners
Because grape seed extract can act as a blood thinner, it could increase your risk of bleeding if you are already taking blood thinners such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin.
Amounts and Dosage
There is no set recommended dosage of grape seed extract to achieve its possible benefits. Because herbal supplements aren’t regulated, you’ll want to be careful to choose a product from a reputable supplier and read the label carefully. As with other supplements, you should avoid using more than is noted on the label or combining multiple forms of this product, which can increase the risk of taking too much.
If you’re considering adding this supplement to your routine, talk to your doctor to be sure you’re selected a safe product and to get their help determining the amount that is right for you.