Starvation refers to two different things：prolonged lack of food and protracted insufficient intake of food.

Prolonged lack of food cannot provide the body with enough nutrient substance, leading to insufficient production of qi and blood and sudden decline of the visceral functions with the manifestations of dizziness and lassitude of the four limbs or even death in severe cases. Protracted insufficient intake of food will lead to malnutrition, deficiency of qi and blood, weakness of the body, susceptibility to invasion of pathogenic factors and various diseases.

Overeating means two different things, crapulence and protracted excessive intake of food. Crapulence impairs the spleen and stomach because the food taken is beyond the normal functions of the spleen and stomach to digest, transport and transform, leading to gastric and abdominal distension and fullness, eructation with fetid and acid odor, anorexia, vomiting and diarrhea, etc. In severe cases the intestinal and gastric vessels and collaterals will be impaired, causing abdominal pain or hemorrhoid bleeding, etc. 

Protracted excessive intake of food will bring on supernutrition, delayed transformation of qi and failure of the nutrients of food and water to transform into qi and blood. Instead, the nutrients of food and water turn into phlegm and accumulate in the body to hinder the flow of qi and blood, leading to obesity, dizziness, palpitation and chest oppression; or transforming dampness into heat to invade the vessels and causing abscess, carbuncle, sores and ulcers, etc.