We can learn a lot from poop. Seriously, hear me out. What comes out can tell us a lot about what’s going on inside. Color, consistency, appearance, and odor are all indications of how healthy, or unhealthy, you are. Think of it like reading tea leaves, except with hard science to back it up.
So What Can We Learn from Stool Color?
Brown might be the standard color of bowel movements, but it's not the only color. Actually, if it comes out another color, it’s a good idea to start asking questions. While it’s probably nothing, you can't be too cautious. The human body isn't like a machine where you can simply take a look under the hood to make sure everything is functioning properly. What you excrete is one of the best indicators of your wellness. Let's take a look at what some common "alternative" colors can mean.
Green stool is not usually a cause for concern; it’s probably just something you ate. Foods high in chlorophyll, like kale and spinach, can lend your voidings that viridian hue. Certain types of algae or other supplements can also cause stool to be green. 
If you're sure, however, that such foods aren't the culprit, it's time to start looking into possible digestive concerns. The liver produces bile, which is green in color, and uses it to break down fats. Stool should pass from the small intestine to the colon, changing color along the way from green to yellow to brown. Green stool could mean that food is passing through the digestive system too quickly and the color change doesn't finish. 
It's worth noting that infants have a much faster bowel transit time than adults. Green stool is common in breastfeeding infants and usually nothing to worry about.
Mucus is the most common cause of white stool and it's not unusual. Mucus traps bacteria and helps waste pass through the colon. If the white disintegrates into the water, it’s likely just mucus. It can also be a sign of fast bowel transit time.   However, kidney health concerns or issues in the biliary system are serious causes of white stool.
Like green stool, yellow stool is common and benign with newborns and something that will pass, pardon the pun.  Yellow stool is not normal for adults. The lone exception to this would be a situation in which a massive amount of yellow food coloring had been recently ingested. If you see yellow stool, organs such as the stomach, liver, large intestine, or small intestine, may be experiencing trouble. See a health professional sooner than later. 
A reddish color can indicate a few things, among them and most important, the presence of blood in your stool. The hue or tone of red in your stool can tell you something about its source. For example, a bright red color may be caused by hemorrhoids or an anal fissure. Other reasons for a red color can be foods like beets and blueberries or excess iron. 
Other Stool Colors
A dark black can indicate that the source of blood is the upper digestive tract. If your stool is dark black, you should seek immediate medical attention.  
Dark brown can result from red wine, excess salt, or not eating enough vegetables.
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†Results may vary. Information and statements made are for education purposes and are not intended to replace the advice of your doctor. If you have a severe medical condition or health concern, see your physician.