Resveratrol: Polyphenol found in grape skins and wine as well as in other foods such as peanuts, blueberries and cranberries. It is believed to be the source of wine's health benefits; studies have linked resveratrol with improved heart health and endurance as well as reduced risk of age-related degeneration, Alzheimer's disease, arthritis, blindness, cancer, obesity and type 2 diabetes.
Polyphenol: Chemical compounds found in plant life. In grapes, polyphenols are responsible for skin pigment, tannins and flavors—all of which fall under the category of flavonoids—as well as resveratrol, the compound associated with many of wine's health benefits, and which falls under the much smaller polyphenol category of non-flavonoids. Pertaining to wine, grape skins, seeds and stems contain the highest concentrations of polyphenols.