Black particles in the stool can be associated with a variety of causes, such as dietary factors, constipation and gastrointestinal tract dysfunction or disease. Patients need to combine their own physical symptoms, to the Department of Gastroenterology stool routine, gastroscopy and other related tests to clarify the cause. 1, food containing melanin food: If the patient has recently taken some food containing melanin can lead to black particles in the stool, common such as black sesame, black fungus, etc., because the coloring material is not absorbed by the gastrointestinal tract, resulting in black particles in the stool. If this is the case, no treatment, just stop eating the above food, the symptoms will then be relieved; 2, intake of iron supplements or iron-containing food: If the patient takes food containing iron or iron supplements, this symptom can also occur, not absorbed iron, the formation of black iron sulfide in the intestines, the discharge of feces is black or contains black particles. This is a normal phenomenon, no need to worry, after the iron supplementation stops, the symptoms will disappear; 3, constipation: patients who have constipation, may also lead to the symptoms of black particles in the stool. As the gastrointestinal tract has the function of digestion and absorption, the fecal mass stays in the intestine for a long time and the water is absorbed in large quantities, which may lead to black or dark stools, or black particles. It is recommended that constipated people, daily drink more water, eat more corn, purple potatoes and other coarse grains, eat more fruits and vegetables, eat less cake, cream, chocolate and other high-sugar, high-fat food, more exercise, avoid sedentary, constipation can generally be relieved; 4, gastrointestinal tract dysfunction: If the digestion and absorption function of the gastrointestinal tract is not good, eat some food can not be digested, the discharge can be in this form, often accompanied by symptoms of abdominal distension. It is recommended that such people, daily diet pay attention to light, easy to digest, avoid eating spicy and stimulating, cold food, if the gastrointestinal function continues to disorder, should go to the hospital for active treatment; 5, upper gastrointestinal bleeding: if the stool, in addition to black, but also tar-like, need to consider the possibility of digestive system lesions, common such as gastric ulcer, gastritis, gastric cancer, etc., patients need to go to the hospital to clarify the cause, under the guidance of doctors for Patients need to go to the hospital to clarify the cause, and under the guidance of the doctor to carry out medication or surgery.