Potatoes, sweet potatoes and other tubers: nutrition, storage, food safety, preparation and cooking.
Potatoes are relatively low in calories when cooked without much added fat. Per 100 g raw, they provide about 77 kcal, 17.5 g carbohydrate, 2.2 g fiber, 2 g protein and roughly 425 mg potassium; frying changes the picture mainly because the potato absorbs oil.
The green pigment itself is chlorophyll and is not toxic, but greening signals light exposure that can also increase natural potato glycoalkaloids such as α-solanine and α-chaconine.
Finding two small sprouts does not automatically condemn a potato. Look at the whole thing: firm and not green can usually be trimmed; heavily sprouted, green, soft, shriveled or bitter is a throw-it-out potato.