Accoding to the theory of traditional Chinese medicine, obesity results from endogenous and exogenous factors. The former refers to various intrinsic factors (heredity, neuropycbosis, metabolism, endocrine) which affect the regulation of the fat metabolism, and the latter includes hyperphagia and hypoactivity.

Based on its clinical manifestations, obesity pertains to the categories of "fei pang" (overweight) or "tan yin" (fat man). Its etiology is related to congenital defect, over-intake of greasy food, prolonged lying or sitting, deficiency of healthy qi due to protracted illness, and emotional upset. It mainly involves the spleen and muscles, but is closely related to the deficiency of kidney qi. Generally, its pathogenesis is principal deficiency and secondary excess.

Principal deficiency is marked by qi deficiency, mostly deficiency of spleen qi and kidney qi, which may be accompanied with deficiency of heart qi and spleen qi and failure of the liver and gallbladder to control dispersion; secondary excess is mainly the retention of turbid phlegm and fat accompanied with dampness, blood stasis and qi stagnation.