Stool Color

Stool color is an important diagnostic indicator reflecting diet characteristics, and the functioning of the liver, pancreas, gallbladder, and intestines. Normal color ranges from light brown to dark brown, due to the presence of stercobilin pigment—a bilirubin metabolite.

Deviations from normal may indicate the following conditions:

• Light yellow (clay-like): may occur with bile flow disruption, liver pathologies (hepatitis, cirrhosis), bile duct obstruction, or consumption of large amounts of fatty foods.
• Green: found with accelerated intestinal transit (diarrhea), intake of green vegetables, antibiotics, iron supplements, and intestinal infections.
• Black: may indicate digested blood (gastrointestinal bleeding), intake of iron or bismuth medications, or consumption of blueberries or prunes.
• Red: fresh blood in stool can be caused by hemorrhoids, anal fissures, colitis, or tumors in the lower intestine. Color may also be altered by beets or food dyes.
• Orange: may be associated with consumption of carotene-rich foods (carrots, pumpkin) or disturbances in fat and pigment metabolism.
• White (pale): typical for bile flow impairment, intake of radiographic contrast agents, or bile duct obstruction.

Stool color can change due to physiological causes (dietary features), but persistent or sharp changes require attention and consultation with a doctor.