The spleen is said to be at the root of all phlegm production.

TCM does not treat "excess weight" per se; rather it deals with the underlying body condition that may have led to the excess weight. Once the body's balance is restored, the metabolism will process food properly and excess weight should no longer be a problem provided correct foods are eaten in moderate quantities. Specifically, TCM holds that fat or adipose tissue is mostly due to phlegm and dampness evils. The spleen is said to be at the root of all phlegm production and is involved in the transportation and transformation of body fluids and foods. If the spleen becomes damaged by eating too many sweet foods and getting too little exercise, it will fail in its duty to move and transform waste fluids and foods. Instead these metabolic wastes will gather, collect and transform into dampness evils. If dampness evils endure over time, they will congeal into phlegm, and become fat tissue.