Black, smelly and sticky stools may be caused by eating colored food or eating too much greasy and sticky food, in addition, peptic ulcer and medication factors may cause black stools. 1. Dietary factors: patients eating black food, such as animal blood, spinach and other foods can cause black stools, eating too much greasy and sticky food can lead to sticky stools. 2. Peptic ulcer: for example, gastric ulcer, duodenal ulcer and other peptic bleeding can cause black stool. 3. Medications: Taking certain medications, such as iron and bismuth, may also cause black stools. Stool color black and stinky sticky patients need to actively seek medical attention, medication should be under the guidance of the doctor, can not blindly take medication to avoid adverse consequences.