It is true that beets are nutritious thanks to their bright red pigments full of the anthocyanins, which are an anthocyanins. Though one could rightly argue that the nutrition of beets is overhyped. Why? Because the the amount of antioxidants in beets is actually less the the greens which are cut off from their tops. Furthermore, beets are not particularly rich in vitamins. 100 grams (3.5 ounces) provide less than 10% of your daily value for vitamin A, C, B-6, and 0% for vitamins D, B-12, and vitamin A. Perhaps their biggest benefit is providing the anthocyanins, since the rest of a salad is made up of mostly greens which contain little to none.
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