Stool comes in a range of colors. All shades of brown and even green are considered typical. Only rarely does stool color indicate a possibly serious intestinal condition.

Stool color is generally influenced by what you eat as well as by the amount of bile — a yellow-green fluid that digests fats — in your stool. As bile travels through your digestive tract, it is chemically altered by enzymes, changing the colors from green to brown.

Ask a healthcare professional if you're concerned about your stool color. If your stool is bright red or black — which may indicate the presence of blood — seek medical attention right away.

Stool quality	What it may mean	Possible dietary causes
Green	Food may be moving through the large intestine too quickly, such as due to diarrhea. As a result, bile doesn't have time to break down completely.	Green leafy vegetables, green food coloring, such as in flavored drink mixes or ice pops, iron supplements.
Light-colored, white or clay-colored	A lack of bile in stool. This may indicate a bile duct blockage.	Certain medicines, such as antacids with aluminium hydroxide, large doses of bismuth subsalicylate (Kaopectate, Pepto-Bismol), other antidiarrheal drugs, and barium, which is used in X-rays.
Yellow, greasy, foul-smelling	Excess fat in the stool, such as due to a malabsorption condition, for example, celiac disease.	Fatty foods such as deep-fried foods, and sometimes the protein gluten, such as in breads and cereals.
Black	Bleeding in the upper gastrointestinal tract, such as the stomach.	Iron supplements, bismuth subsalicylate (Kaopectate, Pepto-Bismol), black licorice.
Bright red	Bleeding in the lower intestinal tract, such as the large intestine or rectum, often from hemorrhoids.	Red food coloring, beets, cranberries, tomato juice or soup, red gelatin, or drink mixes.

Oct. 10, 2024

Original article: https://www.mayoclinic.org/stool-color/expert-answers/faq-20058080