Poor absorption too thin may be caused by gastrointestinal dysfunction, chronic gastroenteritis, hyperthyroidism and other diseases. You can hang up gastroenterology, nutrition, endocrinology and so on. 1. Gastroenterology: poor absorption, too thin may be digestive diseases, such as chronic gastritis, gastric ulcer, duodenal ulcer, chronic enteritis and other diseases belong to the scope of gastroenterology, endoscopy and other tests to confirm the diagnosis and then treatment. 2. Nutrition: Picky eating, eating less can cause poor absorption, too thin, you can hang up the nutrition department, line trace element examination, adjust the diet structure, dietary diversity. 3. Endocrinology: hyperthyroidism, diabetes and other endocrine system diseases can also be manifested as malabsorption, too thin, it is recommended to consult the endocrinology department, improve the relevant examination, clarify the cause of the disease, targeted treatment. There are many other reasons for poor absorption and thinness, so it is recommended to consult a doctor in a timely manner and follow the doctor’s instructions to avoid delaying the condition.