Farting, i.e. exhausting gas, is mostly a normal physiological phenomenon, and increased or abnormal exhaust is generally not a precursor of cancer. There are many reasons for increased or abnormal flatulence, such as indigestion, insufficient gastric motility, eating a greasy or spicy diet, and so on. In addition, increased flatulence can also occur after catching a cold in the abdomen. Abnormal gas emission is not directly related to cancer, and there is no specific manifestation of gas emission even in rectal cancer patients. If bowel cancer develops to a serious stage, complete intestinal obstruction will occur, and then there will be a manifestation of cessation of flatulence. Therefore, the increase of gas emission is not a precursor of cancer. If the abnormal exhaust continues, it is recommended to go to the hospital in time, so as to clarify the cause of the disease under the guidance of professional doctors, in order to avoid delaying the condition.