Sweet potato is one of the average calorie starch foods (provide just 90 calories/100 g vs. 70 calories/100 g of potato). The tuber, however, contains no saturated fats or cholesterol and is rich source of dietary fiber, anti-oxidants, vitamins, and minerals.
Its calorie content mainly comes from starch, a complex carbohydrate. Sweet potato has higher amylose to the amylopectin ratio than potato. Amylose raises the blood sugar levels slowly on comparison to simple sugars and therefore, recommended as a healthy food supplement even in diabetes.
The tuber is an excellent source of flavonoid phenolic compounds such as beta-carotene and vitamin A (100 g tuber provides 14187 IU of vitamin A and 8509 µg of β-carotene). The value is one of the highest among the root-vegetables categories. These compounds are powerful natural antioxidants. Vitamin A is also required by the body to maintain integrity of healthy mucus membranes and skin. It is a vital nutrient for acuity of vision. Consumption of natural vegetables and fruits rich in flavonoids helps to protect from lung and oral cavity cancers.
The total antioxidant strength of raw sweet potato measured in terms of oxygen radical absorbance capacity (ORAC) is 902 µmol TE/100 g.
The tubers are packed with many essential vitamins such as pantothenic acid (vitamin B-5), pyridoxine (vitamin B-6), and thiamin (vitamin B-1), niacin, and riboflavin. These vitamins are essential in the sense that body requires them from external sources to replenish. These vitamins function as co-factors for various enzymes during metabolism.
Sweet potato provides a good amount of vital minerals such as iron, calcium, magnesium, manganese, and potassium that are very essential for enzyme, protein, and carbohydrate metabolism.
Sweet potato leaves are indeed more nutritious than the tuber itself. Weight per weight, 100 g of fresh leaves contain more iron, vitamin C, folates, vitamin K, and potassium but less sodium than the tuber.
