Almost all fruits contain potassium ions, just the amount of potassium varies. Potassium ions are found in a variety of foods in nature, just in different amounts in different foods. Some fruits are relatively high in potassium ions, such as bananas, oranges, cherries and dates. Every 100g of banana contains about 358mg of potassium. Some foods are relatively low in potassium ions, such as apples, pears and grapes. Every 100g of apple contains about 119mg of potassium. Potassium ion is an essential element for the human body and will be excreted in small amounts every day, regardless of whether it is ingested or not, so it needs to be supplemented appropriately through food. However, some patients, such as hyperkalemia or patients with excessive decrease in renal function, need to eat as little as possible of foods high in potassium, and other fruits with moderate or low potassium content should also be controlled for intake to avoid aggravating hyperkalemia. If there is hypokalemia, it can be supplemented by consuming fruits rich in potassium ions, but with hypokalemia, the effect of supplementation through food alone may not be obvious, and drugs need to be applied at this time. Medications need to be applied under the guidance of physicians.