Dark stool color but not black may be due to consumption of certain foods, or may be due to taking certain medications, or may be due to diseases. 1. Food-derived causes: mainly blood products, animal offal, a large number of green vegetables, etc. This is due to the hemoglobin in blood products and animal offal, chlorophyll in green vegetables containing iron, stop eating these foods, the situation will improve. 2. Drug-related causes: iron deficiency anemia patients take iron supplements, gastric disease patients take bismuth-containing drugs, etc., generally stop using drugs, stools become darker and the situation will improve. 3. Disease causes: darker stool color may also be the cause of disease. Diseases such as cirrhosis, portal hypertension, gastrointestinal bleeding, peptic ulcer, etc., can also lead to darker stools, which are usually thinner and tarry. These lesions are usually accompanied by other symptoms such as upper abdominal discomfort, acid reflux, belching, nausea and vomiting. If you have abnormal stools, it is recommended that you seek medical attention as soon as possible to identify the cause and treat it promptly so as to avoid delaying your condition and causing adverse consequences.