Saline can clean the mouth, replenish body fluids, replenish electrolytes, and raise blood pressure. However, there is no need for normal people to drink saline. Saline gargling for mouth ulcers and other diseases, can play a role in cleaning the mouth. Sweating more in summer can easily lead to salt loss, drinking light salt water or saline can replenish body fluids, sodium ions and chloride ions of the body. The intake of saline can also increase blood volume, a certain degree of rising high blood pressure. Patients in a dehydrated, hypotensive state should supplement saline. Some people should not drink saline, such as nephritis, heart disease, hypertension, cirrhosis of the liver, etc. These patients should limit salt intake to avoid aggravating the condition. Adopt good living habits in daily life, keep a calm mind, avoid emotional excitement or strenuous exercise, strengthen nutrition, eat more high-protein diet, eat more fruits and vegetables and crude fiber food, and keep bowel movement smooth. Regular health checkups.