One medium potato with skin contains about 161 kilocalories, 88 percent of which is carbohydrate, 10 percent of which is protein, and 1 percent of which is fat.[1] Potatoes contain a broad array of vitamins and minerals but are particularly rich in potassium, manganese, vitamin C, and vitamin B6.[1] On a calorie-for-calorie basis, potatoes contain about as much fiber as whole grains — 3.8 grams per medium potato with skin.[1]
Percent of daily value per 100 calories
Among plant foods, potato protein stands out as being unusually complete and digestible.[2] In other words, it has an amino acid profile similar to what the human body needs to maintain itself and build muscle, while most plant foods have to be combined with other plant or animal foods to achieve this. However, the total amount of protein in potatoes is modest at 4.3 grams per medium spud.[1]
Potatoes contain a significant amount of non-essential phytochemicals. These include polyphenols, especially phenolic acids (also found in coffee) and, in purple potatoes specifically, anthocyanins (also found in blueberries),[3] which are most concentrated in the skin but also present in the flesh.[3] Observational research suggests that foods high in polyphenols, including anthocyanins, may reduce the risk of cardiovascular disease and type 2 diabetes[4][5].
Randomized controlled trials report that these polyphenols found in potatoes reduce blood pressure and improve endothelial function, consistent with the idea that they may lower cardiovascular disease risk.[6][7] However, there is no direct evidence that consuming potatoes prevents cardiovascular events.
Yellow-fleshed potatoes can also contain a significant amount of carotenoids, especially lutein (also found in green vegetables like spinach).[8] Lutein plays a role in preventing and slowing the progression of macular degeneration, a common cause of visual impairment in the elderly.[9]