Although they have the word yam in their name, Jewel yams are actually a variety of sweet potatoes. Don’t think of these tubers as just another potato. According to nutritionists at the Center for Science in the Public Interest (CSPI) this deliciously sweet and flavorful potato ranks number one in nutrition of all vegetables. A one cup serving of sweet potatoes contains 65% of the minimum necessary daily amount of Vitamin C. Sweet potatoes are also high in calcium, folate, potassium and beta-carotene. Beta-carotene is an antioxidant which converts to Vitamin A in the body: one serving of sweet potatoes can provide you with as much as 700% of the US RDA for Vitamin A. To gain the maximum health benefits from eating sweet potatoes, avoid discarding their skins as this is where much of their healing potential is stored. The intensity of the sweet potato's yellow or orange flesh color is directly correlated to its beta-carotene content.