They are actually a completely different vegetable than regular potatoes.
It’s true that both of them have their place in a healthy diet but these two foods offer different tastes and unique nutritional benefits
Sweet potatoes are loaded with nutrients and have impressive array of antioxidants. Sweet potatoes are also higher in fiber and they have a lower glycemic index which is important for diabetics and carbohydrate watchers.
https://www.eatlikemira.com/2010/05/29/glycemic-index-for-diabetics/
SWEET POTATOES:
1. Sweet potato is very rich in Vitamin A (beta-carotene) and Vitamin C which are powerful antioxidants that work in the body to remove chemicals that damage cells.
2. Sweet potato is good for stomach ulcers and flatulence and colon problems.
3. Sweet potato is loaded with potassium and so is a food remedy for people with high blood pressure.
4. Because of its high fiber content, it fights against constipation and colon cancer
5. Sweet potato is a good food for people involved in heavy muscular work, since it is high in essential vitamins and minerals.
6. Sweet potato is a good food for diabetics, because it helped stabilize blood sugar levels. It is counted as a low glycemic index food.
According to Dr. Mirkin:
7-ounce white potato with skin: 220 calories, 5g protein, 51g carbs, 20mg calcium, 115mg phosphorus, 2.8mg iron, 16mg sodium, 844mg potassium, 4g fiber, .22mg thiamin, .07mg riboflavin, 3.3mg niacin, 16mg vitamin C
7-ounce sweet potato: 208 calories, 3.5g protein, 49g carbs, 56mg calcium, 110mg phosphorus, 1mg iron, 20mg sodium, 693mg potassium, 5g fiber, 4350 RE vitamin A, .14mg thiamin, .13mg riboflavin, 1.2mg niacin, 49mg vitamin C.
One difference not discussed above is that the glycemic index is quite different at 85 (high) for white potato and 54 (medium) for sweet potato.