While 89% of Americans consider bananas to be a significant source of potassium, only 27% associate potatoes with potassium and yet a potato has nearly twice the amount of potassium per serving (759 mg) as a banana (422 mg). Potassium plays a critical role in lowering blood pressure, and about 70 million Americans have high blood pressure. According to a recent study in the Journal of the American College of Cardiology, adding just 1600 mg of potassium a day to your diet can lower your risk of stroke by 21%. One medium Idaho® potato contains 759 milligrams of potassium and provides roughly 25% of the recommended daily dose of this essential nutrient.