Most cases of black stools are from eating black foods or iron
supplements. The most common condition causing black stools is a bleeding ulcer
. Black stools caused by blood indicate a problem in the upper digestive tract. If blood in the stool is suspected, you should contact your doctor as soon as possible
You can help lessen the occurrence of bloody or tarry stools by drinking plenty of water and eating lots of fiber. Water and fiber help soften stool, which can ease the passage of stool from your body. Some foods that have fiber include: raspberries.