Potatoes have a high carbohydrate content and include protein, minerals (particularly potassium), and vitamins, including vitamin C.

Freshly harvested potatoes retain more vitamin C than stored potatoes. New and fingerling potatoes offer the advantage that they contain fewer toxic chemicals. Such potatoes offer an excellent source of nutrition.

Peeled, long-stored potatoes have less nutritional value, although they still have potassium and vitamin C. Potatoes also provide starch, flour, alcohol (see Poitin), dextrin, and livestock fodder. Potatoes (particularly mashed potatoes) are known to have a high Glycemic index, a disqualifying factor in many diets.