A plain baked potato without skin has about 110 calories, according to the Washington State Potato Commission. The potato, a starchy vegetable, contains manly essential nutrients, including potassium. Eating the skin of the potato adds needed fiber but few calories.

The flesh of a 6-oz. baked potato contains 110 calories. Topping a baked potato with 1 tbsp. of butter or margarine adds 100 calories. A tablespoon of sour cream adds another 30 calories.

Potatoes are rich in nutrients. One baked potato has as much potassium as a banana, as well as 45 percent of your daily vitamin C requirement. Potatoes are also good sources of plant protein with 3 g.

The skin of the potato adds few calories but provides 2 g of dietary fiber, an essential part of a healthy diet. Leaving the skin off does not deprive you of nutrition since the potato flesh contains plenty of vitamins and minerals, but including it helps your digestive system run more smoothly.