The woman is very thin but her stomach is very large, mostly due to indigestion, uterine contraction, fat accumulation or gastrointestinal tumors, as follows: 1, indigestion, digestive function of the gastrointestinal reduced, can not eat into the diet in a timely manner digestion, absorption, food in the body a lot of stagnation, intestinal contents can not be discharged out of the body will lead to abdominal distension. The nutrients in the food can not be absorbed, so the body will appear the symptoms of thinning. 2, uterine contraction, if the belly after the birth of a child, mostly because of the contraction of the uterus caused by poor. 3, fat accumulation, often sedentary, do not pay attention to exercise fat is easy to accumulate in the stomach, you can choose yoga, sit-ups to lose fat. 4, gastrointestinal benign and malignant tumors, benign tumors The tumor is movable and will produce pressure on the surrounding tissues, while malignant tumor will be accompanied by fever, body wasting and weakness of limbs.