During a TCM consultation, doctors will often tell patients that you have “dampness”, especially during the yellow plum season in Shanghai. There are few patients with gastrointestinal diseases clinically identified as “dampness” by Chinese medicine practitioners. What exactly is “dampness”? What does it have to do with gastrointestinal disease? In fact, “wet” is a pathological factor in Chinese medicine, it can be due to the feeling of external dampness, for example, some people live in a humid environment for a long time will easily feel the dampness. It can also be generated internally because of the weakness of the spleen and stomach, which cannot transport and transform properly. Therefore, “dampness” is closely related to the spleen and stomach. A thick and greasy tongue is an important basis for determining the presence of “damp” evil. At the same time, the patient often has symptoms such as bitter mouth, sticky mouth, sweet mouth, distended stomach and abdomen, loss of appetite, and loose and unpleasant stools. The treatment of dampness is often based on strengthening the spleen and stomach, and helping to transport and transform dampness. In life, patients should eat a light diet, avoid greasy and spicy food, and eat less sweets.