Quite a lot! New research has suggested that the unsaturated fat that is present in peanuts are helpful for controlling heart disease. Peanuts have many nutritional benefits and they provide an excellent snack time option. Since they are healthy they do not cause any problems. Peanuts can provide good energy and help sustain you through the day. Of course too much of anything is not good and one has to make sure that they don't over eat peanuts. On an average around 28 grams of peanuts will contain around 166 calories. Peanuts also contain minerals such as iron, manganese and calcium.