Perhaps best known for their rich omega 3 content, walnuts are also an excellent source of antioxidants. In fact, out of the 10 most common nuts consumed in the United States, walnuts rank as #2 for antioxidant content, second only to the amount found in pecans.
ORAC Source
USDA Database for the Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods, Release 2 - Prepared by Nutrient Data Laboratory, Beltsville Human Nutrition Research Center (BHNRC), Agricultural Research Service (ARS), U.S. Department of Agriculture (USDA) - May 2010