- Stool color that is strange or different than normal
- Normal stool colors are any shade of brown, tan, yellow or green
- The only colors that may be caused by a disease are red, black and white
- Dark green may look like black, but dark green is a normal color
Causes of Unusual Stool Color
- Almost always due to food coloring or food additives.
- Stool color relates more to what is eaten than to any disease.
- In children with diarrhea, the gastrointestinal (GI) passage time is very rapid. Stools often come out the same color as the fluid that went in. Examples are Kool-Aid or Jell-O.
- The only colors we worry about are red, black (not dark green) and white.
Clues to Unusual Stool Colors
- "Bloody stools": 90% of red stools are not caused by blood
- Blood from lower GI tract bleeding
- Medicines. Red medicines (like Amoxicillin). Sometimes, other medicines that turn red in the GI tract (such as Omnicef)
- Foods. See list below.
Foods That Can Cause Red Stools:
- Red Jell-O, red or grape Kool-Aid
- Red candy, red licorice
- Red cereals
- Red frosting
- Red food coloring
- Fire Cheetos
- Red peppers
- Tomato juice or soup, tomato skin
- Blood from stomach bleeding (stomach acid turns blood to a dark, tar-like color)
- Foods. Licorice, Oreo cookies, grape juice
- Medicines. Iron, bismuth (Pepto-Bismol)
- Other. Cigarette ashes, charcoal
- Bile. Dark green stools from bile may look black under poor lighting. Smear a piece of stool on white paper. Look at it under a bright light. This often confirms that the color is really dark green.
- Green stools are always normal, but they can be mistaken for black stools.
- Bile. Most dark green stools are caused by bile.
- Green stools are more common in formula fed than breastfed infants. It can be normal with both.
- Green stools are more common with diarrhea. This is due to a fast transit time through the gut. However, formed stools can also be green.
- Dark green stools may look black under poor lighting. Eating spinach can cause dark green stools.
- Medicines. Iron (such as in formula)
- Foods. See list below.
Foods That Can Cause Green Stools:
- Green Jell-O
- Grape-flavored Pedialyte (turns bright green)
- Green fruit snacks
- Spinach or other leafy vegetables
White or Light Gray:
- Foods. Milk-only diet
- Medicines. Aluminum hydroxide (antacids), barium sulfate from barium enema
- Liver disease. Babies with blocked bile ducts have stools that are light gray or pale yellow.