Stagnation is generally the accumulation of ingested food in the stomach, intestines, spleen and stomach that cannot be digested, causing a burden on the digestive system of the spleen, stomach and intestines and causing some symptoms, such as abdominal distension, abdominal pain, and dry stools that do not come out, which are symptoms of stagnation. The stagnation will lead to some symptoms other than digestion, such as condensation of dampness into heat and gathering of dampness into phlegm, which are invisible evils in Chinese medicine. Once the dampness, heat, phlegm and dampness are formed, you will find that the tongue coating is yellow and greasy or thick and greasy, which will cause dampness and heat changes in the long run, and will have a certain impact on the whole digestive system or circulatory system, which will cause toxins not to be discharged over time and cause hyperlipidemia, hypertension or abdominal obesity.