Benefits of Grapes
Grape seed extract (GSE) is 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) and is one of the best-known sources of proanthocyanidins. Due to its high antioxidant content, GSE can help prevent disease and protect against oxidative stress, tissue damage, and inflammation. Ten health benefits of grape seed extract that are based on science are the following:
- Can reduce blood pressure
Several studies have researched the effects of GSE in high blood pressure. A review of 16 studies in 810 people with high blood pressure 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.
- Can improve blood flow
Some studies suggest that GSE may improve blood flow. In an eight 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 eight healthy young women assessed the effects of a single 400-mg dose of proanthocyanidin from GSE immediately followed by six hours of sitting. It was shown to reduce leg swelling and edema by 70%, compared with not taking GSE. In the same study, eight 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.
- Could reduce oxidative damage
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. GSE supplements have been found to reduce LDL oxidation triggered by high fat diets in several animal studies. Research in humans shows similar results. When eight healthy people ate a high fat meal, taking 300 mg of GSE inhibited the oxidation of fats in the blood, compared with a 150% increase seen in those who did not take GSE. In another study, 61 healthy adults saw a 13.9% reduction in oxidized LDL after taking 400 mg of GSE. 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.
- May improve collagen levels and bone strength
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. 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. Rheumatoid arthritis is an autoimmune condition that results in severe inflammation and the destruction of bone and joints. Animal studies have shown that GSE may suppress bone destruction in inflammatory autoimmune arthritis. GSE also significantly reduced pain, bony spurs, and joint damage in osteoarthritic mice, improving collagen levels and reducing cartilage loss.
- Supports your brain as it ages
Flavonoids’ combination of antioxidant and anti-inflammatory properties are thought to delay or reduce the onset of neurodegenerative diseases like Alzheimer’s disease. 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. Clusters of beta-amyloid proteins in the brain are characteristic of Alzheimer’s disease. Animal studies have found that GSE may prevent memory loss, improve cognitive status and brain antioxidant levels, and reduce brain lesions and amyloid clusters. 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.
- Can improve kidney function
Your kidneys are particularly susceptible to oxidative damage, which is often irreversible. Animal studies have shown that GSE may reduce kidney damage and improve function by reducing oxidative stress and inflammatory damage. 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.
- Can inhibit infectious growth
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. In lab studies, GSE has been found to inhibit 43 strains of antibiotic-resistant Staphylococcus aureus bacteria. 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.
- May reduce cancer risk
The causes of cancer are complex, though DNA damage is a central characteristic. A high intake of antioxidants, such as flavonoids and proanthocyanidins, are associated with a reduced risk of various cancers. 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.
- May protect your liver
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. In test-tube studies, GSE reduced inflammation, recycled antioxidants, and protected against free radical damage during toxin exposure. The liver enzyme alanine aminotransferase (ALT) is a key indicator of liver toxicity, meaning that its levels rise when the liver has sustained damage. 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.
- Enhances wound healing and appearance
Several animal studies have found GSE can aid wound healing. 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 eight 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. In another eight week study in 110 healthy young men, a 2% GSE cream improved skin appearance, elasticity, and sebum content, which can help reduce the signs of aging.