Regular Potato vs. Sweet Potato...nutritional differences?

Hey, all. A friend of mine had heard that sweet potatoes have a lower carb content, and a different caloric content, than regular potatoes. Can anyone confirm, deny, and/or specificy these questions?

Thanks. - Freewill39.

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I would just add that the fact that we call them both “potatoes” does not mean they’re particularly closely related; the sweet potato being a member of the morning glory family (don’t know if there are any other edible members), and the “regular” potato being a member of the nightshade (tomatoes, peppers, eggplants) family.

Also for some reason, sweet potatoes are more acceptable in controlled carb diets. On South Beach you should eat sweet potatoes instead of regular, I think. From what I remember, that is. I guess it’s got a lower glycemic index value, or something.