Stool color vary in colors, and for all sorts of reasons. While the shades of brown to green are what is considered normal, the color is affected by the food we ingest. The presence of bile in our stool is actually a huge factor. Bile, that is, the digestive juice secreted by our liver to digest fat and is yellow-green in color, change in pigmentation as they travel along the intestines. Bile is primarily the reason for normal stool color being brown.
That is all to say that it is rarely ever the case that stool color is indicative of a serious disease or an intestinal condition.
Let’s look at some of common stool colors and their potential causes.
Green is a common stool color change. Eating green and leafy vegetable such as kale or spinach, iron supplements, or food with green food coloring all potentially causes stool to pigment into the color green.
Green stool may also indicate diarrhea. Under this condition, food moves quickly through the large intestine, without the time to have bile break down completely.
White or Light-Colored Stool
Stool that range from white to light or clay-colored may be indicative of a lack of bile in the stool. As bile is produced in the liver and kept in the gallbladder, diseases in these organs of the body might impede the bile from getting to the stool. Any obstruction in the bile ducts, or the tubes that carry the bile along the small intestines, can also cause the lack of bile. Tumor, gallstone, or a condition termed as biliary artesia are serious potential illness that may have raised to cause this.
Ingesting certain medications in large doses may also help explain this. Bismuth subsalicylate (e.g. Pepto-Bismol, Kaopectate) and anti-diarrhea medications has been known to cause stool to be light-colored.
Especially when coupled with an excessively malodorous scent and the abnormal presence of grease, this may indicate excessive fat that may be due to a more serious malabsorption disorder, such as celiac disease. People who have celiac and happen to eat gluten, a protein found in bread and cereals or in any food with wheat, rye or barley, will have a problematic time digesting their food. Do not hesitate to ask for evaluation from a medical professional if this has been the case for you.
In other situations, as with infants who breastfeed, having yellow-colored stool is normal.
Infants’ stool is often this color for a few days after being born. Other than that, some more common explanation for having black stool include taking iron supplements and bismuth subsalicylate, or just eating blackberries or black licorice.
However, this is also a sign of bleeding in the upper gastrointestinal tract, such as the stomach. Bleeding in the upper digestive tract can itself be caused by a variety of reasons: cancer, non-cancerous tumor, ulcer, or bleeding sores in the esophagus due to acid reflux.
Bright Red-Colored Stool
Another sign of internal bleeding is having bright red stool, but in this case, on the lower part of the gastrointestinal tract, such as in the large intestine or the rectum. It is often due to hemorrhoids, but may also be to colitis, noncancerous tumors, polyps in the colon, a condition called diverticular disease, or cancer.
Or, it may as well also be because of eating food with red food coloring. Eating red food, including tomato juice or soup, red gelatin, beets and drink or food with red food coloring. may cause stool to be this color.
There is no need to panic as soon as you see a change in pigmentation in your stool. The first step is evaluating your meal and find possible causes for the change. Nevertheless, especially for stool colored red or black, never hesitate to consult a doctor and seek prompt medical attention.
Further reading: Does Your Poop Float or Sink?