Grape seed extract (GSE) is a dietary supplement made by removing, drying, and pulverizing the bitter-tasting seeds of grapes.
Grape seeds are rich in antioxidants, including phenolic acids, anthocyanins, flavonoids, and oligomeric proanthocyanidin complexes (OPCs).
In fact, GSE is one of the best-known sources of proanthocyanidins
Can reduce blood pressure.
Improving blood flow.
Reduce oxidative damage.
Improve collagen levels and bone strength.
Supports your brain as it ages.
Can support kidney function.
Can inhibit infectious growth.
May reduce cancer risk.
Protect your liver.
Enhances wound healing and appearance.
Read more below…
Several studies have researched the effects of GSE on high blood pressure.
A review of 16 studies in 810 people with high blood pressure or an elevated risk of it found that taking 100–2,000 mg of GSE daily significantly reduced systolic and diastolic blood pressure (the top and bottom number) by an average of 6.08 mmHg and 2.8 mmHg, respectively.
Those under the age of 50 with obesity or a metabolic disorder showed the greatest improvements.
The most promising results came from lower doses of 100–800 mg daily for 8–16 weeks, rather than a single dose of 800 mg or more.
Another study in 29 adults with high blood pressure found that taking 300 mg of GSE daily lowered systolic blood pressure by 5.6% and diastolic blood pressure by 4.7% after 6 weeks
Some studies suggest that GSE may improve blood flow.
In an 8-week study in 17 healthy postmenopausal women, taking 400 mg of GSE had blood-thinning effects, potentially reducing the risk of blood clots.
An additional study in 8 healthy young women assessed the effects of a single 400-mg dose of proanthocyanidin from GSE immediately followed by 6 hours of sitting. It was shown to reduce leg swelling and edema by 70%, compared with not taking GSE.
In the same study, 8 other healthy young women who took a daily 133-mg dose of proanthocyanidins from GSE for 14 days experienced 40% less leg swelling after 6 hours of sitting
An elevated blood level of LDL (bad) cholesterol is a known risk factor for heart disease.
The oxidation of LDL cholesterol significantly increases this risk and plays a central role in atherosclerosis, or the buildup of fatty plaque in your arteries (8Trusted Source).
In another study, 61 healthy adults saw a 13.9% reduction in oxidized LDL after taking 400 mg of GSE. However, a similar study was unable to replicate these results (5Trusted Source, 12Trusted Source).
Additionally, a study in 87 people undergoing heart surgery found that taking 400 mg of GSE the day before surgery significantly reduced oxidative stress. Therefore, GSE likely protected against further heart damage (15Trusted Source).
Increasing flavonoid consumption may improve collagen synthesis and bone formation.
As a rich source of flavonoids, GSE may thus help increase your bone density and strength.
In fact, animal studies have found that adding GSE to either a low calcium, standard, or high calcium diet can increase bone density, mineral content, and bone strength (16Trusted Source, 17Trusted Source).
Rheumatoid arthritis is an autoimmune condition that results in severe inflammation and the destruction of bone and joints.
GSE also significantly reduced pain, bony spurs, and joint damage in osteoarthritic mice, improving collagen levels and reducing cartilage loss (21Trusted Source).
Despite promising results from animal research, human studies are lacking.
One of the components of GSE is gallic acid, which animal and lab studies have shown can inhibit the formation of fibrils by beta-amyloid peptides (23Trusted Source).
Clusters of beta-amyloid proteins in the brain are characteristic of Alzheimer’s disease (23Trusted Source).
Animal studies have found that GSE may prevent memory loss, improve cognitive status and brain antioxidant levels, and reduce brain lesions and amyloid clusters (24Trusted Source, 25Trusted Source, 26Trusted Source, 27Trusted Source).
One 12-week study in 111 healthy older adults found that taking 150 mg of GSE daily improved attention, language, and both immediate and delayed memory (28Trusted Source).
However, human studies on the use of GSE in adults with preexisting memory or cognitive deficits are lacking.
Your kidneys are particularly susceptible to oxidative damage, which is often irreversible.
In one study, 23 people diagnosed with chronic renal failure were given 2 grams of GSE daily for 6 months and then compared with a placebo group. Urinary protein decreased by 3% and kidney filtration improved by 9%.
This means that the kidneys of those in the test group were much better able to filter urine than the kidneys of those in the placebo group (32Trusted Source).
GSE displays promising antibacterial and antifungal properties.
Studies have shown that GSE inhibits the growth of common foodborne bacteria, including Campylobacter and E. coli, both of which are often responsible for severe food poisoning and abdominal upset (33, 34).
In lab studies, GSE has been found to inhibit 43 strains of antibiotic-resistant Staphylococcus aureus bacteria (35Trusted Source).
Candida is a common yeast-like fungus that can sometimes result in candida overgrowth, or thrush. GSE is widely used in traditional medicine as a remedy for candida.
In one study, mice with vaginal candidiasis were given an intravaginal GSE solution every 2 days for 8 days. The infection was inhibited after 5 days and gone after 8 (36Trusted Source).
Unfortunately, human studies on GSE’s ability to help treat infections are still lacking.
The causes of cancer are complex, though DNA damage is a central characteristic.
The antioxidant activity of GSE has shown potential to inhibit human breast, lung, gastric, oral squamous cell, liver, prostate, and pancreatic cell lines in lab settings (38Trusted Source, 39Trusted Source, 40Trusted Source, 41Trusted Source).
A review of 41 animal studies found that either GSE or proanthocyanidins reduced cancer-induced toxicity and damage in all but one of the studies (44Trusted Source).
Keep in mind that the anticancer and chemopreventive potential of GSE and its proanthocyanidins may not be directly transferable to people with cancer. More studies in humans are needed.
Your liver plays an important role in detoxifying harmful substances introduced to your body through drugs, viral infections, pollutants, alcohol, and more.
GSE appears to have a protective effect on your liver.
The liver enzyme alanine aminotransferase (ALT) is a key indicator of liver toxicity, meaning that its levels rise when the liver has sustained damage (37Trusted Source).
In one study, 15 people with non-alcoholic fatty liver disease and subsequent high ALT levels were given GSE for 3 months. Liver enzymes were monitored monthly, and results were compared with taking 2 grams of vitamin C per day.
After 3 months, the GSE group experienced a 46% reduction in ALT, while the vitamin C group showed little change (49Trusted Source).
Human studies show promise as well.
In one such study, 35 healthy adults who had undergone minor surgery were given either a 2% GSE cream or placebo. Those using the GSE cream experienced full wound healing after 8 days, while the placebo group took 14 days to heal.
These results are most likely due to high levels of proanthocyanidins in GSE triggering the release of growth factors in the skin (53Trusted Source).