Is that a sweet potato? Or is that a yam? Good question! I was confused myself for so long. But now I know there is a distinction. That orange colored flesh of the picture on the left is the sweet potato, though it is often labeled as a "yam." It comes from the plant family known as Convovulaceae, or Morning Glory. It is very different from the yam that comes from the Caribbean, which is an edible root of the Discorea genus. The true yam is rough and scaly. And its nutrient content is much different from the sweet potato. There are several varieties and colors of the sweet potato. To make matters even worse, the sweet potato is not a potato either!
SWEET POTATO'S NUTRITIONAL VALUE
The sweet potato is considered one of the most nutritious vegetables around. It is nutritionally unique from the potato and the yam. It is very high in beta-carotene, providing several times the recommended daily allowance of Vitamin A. This root vegetable is also packed with potassium, manganese and copper. It is a good source of vitamins C and B6. The sweet potato is high in fiber but you have to eat the skin!
The white potato is a species belonging to the nightshades. These are foods that cause inflammation that are especially a problem for those with arthritis and other inflammatory conditions. Other nightshades include tomatoes, eggplant, capers and peppers. Fortunately, the sweet potato is NOT a nightshade. In fact they contain quercetin, which is a powerful anti-inflammatory.