Bloating for a few years does not confirm the diagnosis of bowel cancer. Bloating is a clinical manifestation and symptom, and does not single-handedly confirm the diagnosis of any disease. Apart from bowel cancer, most of the bloating is caused by indigestion, gastrointestinal dysfunction, chronic gastritis, enteritis and other diseases. 1. Indigestion: mostly due to overeating and not paying attention to diet and life habits, patients may manifest symptoms such as bloating, nausea, vomiting, etc. Patients not paying attention to diet and life habits may lead to repeated bloating. 2. Gastrointestinal dysfunction: due to the interaction of biological, psychological and social factors, it can manifest as abdominal pain, diarrhea, constipation, nausea and so on. Under the effect of the above triggers, it can manifest as repeated abdominal distension and other symptoms. 3. Chronic gastritis and enteritis: it can manifest as abdominal distension, diarrhea, loss of appetite, emaciation and other symptoms. Inflammation stimulation caused by patients not paying attention to eating habit and living habit can lead to repeated abdominal distension. In addition to abdominal distension, bowel cancer may manifest symptoms such as change of stool trait and habit, palpation of abdominal mass, blood in stool, abdominal pain, emaciation and so on. It is necessary to go to the hospital for relevant examination to confirm the diagnosis, and one should not diagnose and treat the disease by oneself.