Scavenging or quenching of the reactive oxygen species (ROS) involved in oxidative stress has been the subject of many recent studies. Resveratrol, found in various natural food products, has been linked to decreased coronary artery disease and preventing cancer development. The present study measured the effect of resveratrol on several different systems involving the hydroxyl, superoxide, metal/enzymatic-induced, and cellular generated radicals. The rate constant for reaction of resveratrol with the hydroxyl radical was determined, and resveratrol was found to be an effective scavenger of hydroxyl, superoxide, and metal-induced radicals as well as showing antioxidant abilities in cells producing ROS. Resveratrol exhibits a protective effect against lipid peroxidation in cell membranes and DNA damage caused by ROS. Resveratrol was also found to have a significant inhibitory effect on the NF-kappaB signaling pathway after cellular exposure to metal-induced radicals. It was concluded that resveratrol in foods plays an important antioxidant role.