Common causes of low potassium include insufficient potassium intake, excessive potassium excretion and primary aldosteronism. 1. Insufficient potassium intake: Because of long-term weight loss, serious partiality and anorexia, which leads to a decrease in the body’s food intake of potassium. If the daily intake of potassium is less than 3 grams for a long time, potassium deficiency will occur. 2. Excessive potassium excretion: Patients who have severe diarrhea or vomiting with large amount of digestive fluid loss will probably lead to potassium deficiency. Prolonged or heavy use of diuretics in daily life may also lead to renal potassium loss, which usually occurs in adults. 3. Primary aldosteronism: Low potassium in primary aldosteronism may be caused by suprarenal cortex tumors or hyperplasia of the suprarenal cortex, in which the body secretes excessive aldosterone, leading to the symptoms of low potassium. There are many clinical factors leading to low potassium, and patients should develop good living habits and use medication correctly under the guidance of professional doctors.