Gravinol is an antioxidant that contains grape seed polyphenol (the primary component of which is Proanthocyanidin) as an active ingredient. (Gravinol is included on lists of food additives as a grape seed extract.)

Data has been published on its various physiological functions, such as its ability to suppress arteriosclerosis, to suppress the development process of colon cancer, to prevent diabetes and its complications, to prevent oxidative stress, and to control loss of muscle strength during exercise.