Potassium is a mineral that helps the kidneys function normally. It also plays a key role in cardiac, skeletal, and smooth muscle contraction, making it an important nutrient for normal heart, digestive, and muscular function. A diet high in potassium from fruits, vegetables, and legumes is generally recommended for optimum heart health.
Having too much potassium in the blood is called hyperkalemia and having too little in the blood is known as hypokalemia. Proper balance of potassium in the body depends on sodium. Therefore, excessive use of sodium may deplete the body's stores of potassium. Other conditions that can cause potassium deficiency include diarrhea, vomiting, excessive sweating, malnutrition, and use of diuretics. In addition, coffee and alcohol can increase the amount of potassium excreted in the urine. Adequate amounts of magnesium are also needed to maintain normal levels of potassium.
For most people, a healthy diet rich in vegetables and fruits provides all of the potassium needed. The elderly are at high risk for developing hyperkalemia due to decreased kidney function that often occurs as one ages. Older people should be careful when taking medication that may further affect potassium levels in the body, such as nonsteroidal anti-inflammatories (NSAIDs) and ACE inhibitors .