Purple sweet potato is rich in cellulose and various nutrients, which helps to lose weight, prevent constipation and keep healthy. Purple sweet potato is a low-calorie food. Every 100g of purple sweet potato contains about 1 16 calories. Purple potato is rich in dietary fiber, which can provide 2.5 grams of fiber per 100 gram. Purple sweet potato is also rich in vitamin A, vitamin C, anthocyanin and other nutrients. Vitamin A helps to maintain the health of eyesight and immune system, and vitamin C has antioxidant effect. Anthocyanins play an important role in anti-inflammatory and anti-oxidation.