Potassium is an electrolyte, which means that it carries an electrical charge. In this role, it stimulates nerve impulses and muscle contractions. It also helps regulate your heart beat. Another important job filled by potassium is its ability to lower blood pressure. Eating too much salt increases your blood pressure, but if you get enough potassium every day, it can help offset the damage from salt. Adults should consume 4,700 milligrams of potassium daily, but most Americans get barely half that amount, according to the U.S. Department of Agriculture. One cup of canned pineapple juice supplies 7 percent of your daily potassium.