The main reason for feeling hungry is the low blood glucose concentration in the blood, generally there are several common causes: 1, diabetes, because of accelerated metabolism leads to hunger, with thirst, drinking, polyuria symptoms. 2, hyperthyroidism, also because of accelerated metabolism, the patient is generally thin, grumpy. 3, gastrointestinal peristalsis is too fast, eat food emptying too fast, leading to hunger. 4, because of the spleen and stomach disharmony leads to damp heat. Food is not digested well in the stomach, in the small intestine absorption disorders, blood sugar concentration in the blood is too low, so there will be hunger. 5, some people with poor liver and kidney function, for food can not be fully digested, absorption, will also cause hunger, you can go to check the liver and kidney function, to exclude systemic diseases and then symptomatic treatment.