Why is My Poop Green? Stool Colors Explained

Poop can be an uncomfortable subject. However, everyone produces it, and it’s an essential part of being human.

The medical name for poop is stool. Merriam-Webster define stool quite simply as “a piece of solid waste that is released from the body.”

Although everybody produces stool, not all stool is the same. In this article, we examine what can affect the color of poop, and whether it is ever a cause for concern.

What affects the color of poop?

The normal color of stool should be a light to dark brown. A substance from red blood cells called bilirubin gets broken down and ends up in the intestines. Bacteria then break it up and turn it brown.

So, what does it means when the color of poop suddenly changes, and what are some of the possible causes?

Changes in diet, including food and drink, may produce varying stool colors. Eating beets, green vegetables, or licorice can significantly change the color of stool. Drinking Guinness or drinks that contain heavy dye such as Kool-Aid can have a similar effect.

There are, however, more serious causes of non-brown stool color which should be dealt with immediately if discovered.

Here is a brief list of potential illnesses that may change the color of stool:

• Tears in the lining of the anus
• Gallbladder disease
• Celiac disease
• Ulcerative colitis – a condition where the top layer of the large intestine lining is inflamed
• Crohn’s disease – a condition where all of the large intestine can become inflamed
• Tumors
• Diverticular disease – a condition where pouches form in the intestine
• Cancers
• Piles (hemorrhoids)
• Bleeding in the gut

It is difficult to consistently relate a precise color to each illness. There are some general characteristics that can serve as a guide, however.

• Reddish stool – can be caused by bleeding in the lower gut or rectum
• Yellowish stool – can indicate an infection in the small intestine
• White or clear – can indicate a lack of bile in the body
• Black or dark brown – could indicate bleeding in the upper gut

People should see a doctor if any discoloration persists instead of trying to work it out for themselves.

Potential causes of green poop

What makes poop green? Green stool is usually the result of a high quantity of leafy, green vegetables in someone’s diet.

People who do not eat a lot of greens should be wary, however, as green poop can have a more serious cause. Stool may be green due to bile pigment in the stool if food moves too quickly through the intestine. This means that the chemical can’t break down sufficiently. One potential cause of this is diarrhea.

People who think their green stool is not the result of a diet rich in vegetables or green food coloring should discuss things with their doctor.

Poop consistencies

It is worth having a quick look at stool before flushing it away. Stool is a very good indicator of whether the digestive system is working properly. If there are any illnesses occurring in the body such as those mentioned above, stool may give a clue.

According to the Bristol Stool Chart, there are seven shapes and formations that characterize our stool. Each one denotes something about a person’s diet or body.

The Bristol Stool Chart

• Type 1: Separate, hard lumps, like nuts (that are often hard to pass)
• Type 2: Sausage-shaped but lumpy
• Type 3: Sausage-shaped but with cracks on the surface
• Type 4: Sausage- or snake-like, smooth and soft
• Type 5: Soft blobs with clear-cut edges (easy to pass)
• Type 6: Fluffy pieces with ragged edges, mushy
• Type 7: Watery, no solid pieces (entirely liquid)

As a general rule, type 3 or 4 is the ideal stool as it is easy to pass without being too watery. Type 1 or 2 means that a person is probably constipated. Type 5, 6, or 7 indicates that a person probably has diarrhea.

This chart helps doctors identify problems, as well as measure the time it takes for food to pass through the digestive system. The shape and form of stool may also help doctors to make a correct diagnosis.

What to look out for with poop

It is important to know what to look out for with respect to the more serious causes of stool discoloration. These can include conditions such as diverticulitis, Crohn’s disease, and cancer, which usually manifest with bleeding from the anus.

Important symptoms to look out for include:

• Dark, tarry stools
• Large amounts of blood passed from the rectum
• Blood in the toilet bowl
• Itchy anus
• Swollen blood vessels in the rectum
• Small tears in the skin of the anus
• An urge to keep passing stools even when the bladder is empty
• A small channel developing between the end of the bowel and the skin of the anus

As well as any traces of blood in the stool, or general bleeding from the anus, pay attention to any other symptoms linked with stool discoloration. These include light-headedness, dizziness, nausea, or vomiting, especially if vomit contains blood as well.

People should seek the advice of a doctor immediately if any of these symptoms persist.

Common causes of rectal bleeding include:

• Piles (hemorrhoids)
• Tears in the lining of the anus
• Anal fistula – a small channel that develops between the end of the bowel and the skin of the anus
• Angiodysplasia – swollen blood vessels in the gut
• Gastroenteritis – inflammation of the gut
• Diverticular disease
• Bowel cancer (colon or rectal cancer)

Less common causes of rectal bleeding include:

• Drugs that treat blood clots
• Inflammatory bowel disease
• Bowel polyps – small growths that are usually harmless
• Sexually transmitted infections (STIs)

The take home

The most important thing to do to regulate stool color is to eat healthily. As discussed earlier, the ideal stool color is light to dark brown. Some people who have a high quantity of greens in their diet may pass poop that has a green color too.

Having green poop isn’t usually a cause for concern. It is important for people to keep an eye on both the color and the texture of their stool, however. Anyone who is concerned with the color of their stool should discuss it with their doctor.