Overeating or hunger: Voracious eating or hunger may give rise to disease. Hunger causes malnutrition and leads to an insufficient supply of qi and blood, which causes general body weakness. Overeating damages the digestive and absorptive functions, and manifests the symptoms of epigastric and abdominal distension and pain, belching, acid regurgitation, anorexia, vomiting, diarrhea, etc.

Partiality for a particular kind of food: Food intake should be varied. In this way necessary nutrient substances are guaranteed. Partiality to a particular food may bring on disease due to insufficient nutrients. For example: long-term intake of polished white rice may cause beriberi; long-term drinking of iodine-deficient water may cause goiter; indulgence in spicy or boiling hot food may give rise to dryness of the mouth, halitosis, diabetes, etc.; indulgence in smoking, alcoholic drinks, or greasy and highly flavored food may produce pathological phlegm indigestion, stuffy chest, excessive sputum, or boils and ulcers.