Participants were asked to consume an antioxidant supplement including carotenoids, mixed tocopherols, vitamin C and selenium, or a placebo for 8 weeks. The doses of antioxidants will be similar to the amounts suggested by the United States Department of Agriculture (USDA) recommended daily allowances (RDA). In addition, a group of participants will be asked to change their usual eating habits and consume more of certain foods that are naturally good sources of the four antioxidants contained in the pills.