What's wrong with black shit?

The patient's feces were black. It was possible that the patient had eaten a lot of animal blood recently, or had taken iron or secretions. As long as the body did not feel uncomfortable, there was generally no need to worry. He usually ate more digestible foods, fruits and vegetables. However, if he showed stomach discomfort or even stomachache, he needed to go to the hospital for a check-up to see if he showed stomach ulcers and bleeding.