Potassium is an important element in human body, which mainly exists in human cells. It cooperates with extracellular sodium to maintain osmotic pressure and acid-base balance inside and outside cells, thus maintaining nerve and muscle functions, especially the normal activities of myocardium. In the hot summer, due to a lot of sweating, potassium excretion increases, coupled with less sleep, poor appetite and less eating, potassium deficiency will occur to varying degrees, causing fatigue, loss of appetite, heat resistance and physical decline. When potassium is seriously deficient, there will be symptoms such as acid-base imbalance, metabolic disorder, arrhythmia and general weakness. Drinking too much salt and boiled water will easily increase the burden on the heart and unbalance the ratio of potassium to sodium in the body. Therefore, it is very important to supplement potassium properly.