What Grape Seed Extract Is
Derived from the seeds of red wine grapes (Vitis vinifera).
Rich in polyphenols, especially oligomeric proanthocyanidins (OPCs).
Known for strong antioxidant capacity — often stronger than vitamin C or vitamin E in laboratory settings.
 
Mechanisms of Action
Antioxidant: Neutralizes free radicals, protecting DNA, proteins, and lipids from oxidative damage.
Anti-inflammatory: Inhibits NF-κB and other pro-inflammatory signaling pathways.
Vascular effects: Improves endothelial nitric oxide production, supporting blood vessel relaxation and lower blood pressure.
Anti-cancer potential: Lab and animal research shows inhibition of cancer cell proliferation, induction of apoptosis, and reduction of angiogenesis.
Collagen and skin health: Supports collagen synthesis and protects against UV-induced skin damage.
 
Evidence in Cancer
Preclinical studies:
In colon, breast, prostate, and lung cancer models, GSE reduced tumor growth, metastasis, and angiogenesis.
Proanthocyanidins modulate pathways like p53, Bax/Bcl-2, and caspases (apoptosis), and inhibit VEGF (angiogenesis)
 
Regulatory status: GSE is not approved for cancer treatment. Current evidence supports it as a supportive or preventive nutraceutical, not a therapy.
 
Other Health Effects
Cardiovascular health:
May lower systolic blood pressure by ~5 mmHg and diastolic by ~2–3 mmHg.
Improves circulation and reduces oxidation of LDL cholesterol.
Metabolic health: May improve insulin sensitivity and reduce markers of metabolic stress.
Skin and aging: Used in cosmetic products for antioxidant and collagen-preserving effects.
Brain health: Animal models suggest neuroprotective effects, but human data are limited.