Under normal circumstances, phlegm itself is a normal secretion of the human body. Generally speaking, swallowing phlegm will not affect the human body, but the specific situation should be decided according to the patient’s own condition and the composition of the phlegm. 1. Most of the phlegm in the human body is produced by the secretion of the glands in the airway, and the phlegm of healthy people will contain secretion or a small amount of bacterial dust particles, which generally does not have a great impact on the health of the body, and may cause nausea in some people. 2. However, if the sputum contains more tuberculosis bacteria, swallowing it may cause intestinal tuberculosis. Therefore, if the body contains more sputum, you can go to the hospital in time for examination to determine the cause of the disease, so as to carry out targeted treatment.