There is no one "normal" color of stool, as color can be affected by both by food and by the digestive process. As food moves through the digestive tract, it turns from green to yellow-orange to brown. Bile and bacteria is what gives stool its final brown color.
There are several common and benign reasons for passing orange stools. Supplements and medications that can cause orange-colored stools include those containing beta-carotene (sometimes found in vitamin A) and aluminum hydroxide (which can be found in antacids).
Foods that can cause orange stool include:
- Any food with artificial yellow or orange coloring
- Carrots
- Cilantro
- Collard greens
- Fresh thyme
- Kale
- Sweet potatoes
- Spinach
- Turnip greens
- Winter squash
If stool is still orange when it is eliminated, it could mean that it is not being exposed to, or absorbing enough, bile salt. Bile is yellowish green, and when it reacts with enzymes in the bowel, it turns stool brown.
One reason that stool may not be absorbing enough bile is that the stool is moving through the body too quickly. This could be caused by a variety of reasons, including diarrhea, irritable bowel syndrome, or short bowel syndrome. A second cause is a lack of bile, which could mean that the body is not making enough bile, or that the bile ducts are blocked. A blockage in the bile ducts can be caused by gallstones, inflammation, cysts or tumors.
If you can not attribute the color of your stool to a dietary reason, or if you have other symptoms (such as diarrhea, constipation, weakness, or dizziness), consult your physician.
Sources:
ADAM. "Bile duct obstruction." ADAM. 2004. 12 Apr. 2007.
National Institute of Diabetes and Digestive and Kidney Diseases. "Your Digestive System and How It Works." National Institutes of Health. May 2004. 12 Apr. 2007.
Mayo Clinic Staff. "Stool color: When to worry." Mayo Clinic Feb 22 2006. 12 Apr. 2007.
Kevin Pho, M.D. "What could be causing my Autistic son to have orange stools?" MedHelp.org. Sept 17 2003. 12 Apr. 2007.

