A potato is a starchy vegetable, though the starch in potatoes acts very much like dietary fiber. Because it can't be broken down in the digestive system, this starch has the health benefits of fiber, including lowering levels of "bad" cholesterol.
The potato is a member of the nightshade family, and its edible part is an underground tuber. As well as starch, excellent nutrients in potatoes include vitamin B6 and vitamin B3, potassium, copper, vitamin C, manganese, phosphorus, fiber and pantothenic acid. Scientists have also discovered that potatoes contain substances called kukoamines, which have been shown to lower blood pressure in some people.