Grape seed extract (GSE) contains proanthocyanidins, which have been demonstrated to exhibit a wide spectrum of pharmacological, therapeutic, and chemoprotective properties. Studies have demonstrated that GSE can reduce inflammation by inhibiting the formation of inflammatory cytokines and reducing inflammatory mediators. GSE can ameliorate atherosclerosis by reducing inflammation, decreasing MDA-LDL, and decreasing foam-cell formation. GSE has been found to be cytotoxic toward human breast, lung, and gastric adenocarcinoma cells.

Many pharmaceuticals can damage various organ systems. GSE has been studied and has the ability to protect numerous organs from toxicity caused by drugs or chemicals. GSE is a powerful antioxidant that has a wide range of health benefits and has been shown to have better free radical–scavenging ability than vitamins C or E, or beta-carotene.