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What Does a Green Bowel Movement Mean?

Edmund has spent the last ten years working in clinical research. He has written many articles on human anatomy and physiology.

Look before you flush! The appearance of your stool can say a lot about your health.

Look before you flush! The appearance of your stool can say a lot about your health.

What Color Is Your Stool?

Many people don’t pay a lot of attention to the color and texture of their stool—they just flush it down without looking. It can be useful, however, to take a peek. The appearance of your stool can often tell you a good deal about what is happening inside your body.

Green bowel movement is a term used when one’s stool has a greenish color instead of the normal rusty-brown appearance. There are various issues that can lead to a green stool. It can result from the intake of a certain medication, a supplement, or artificially colored food. There may be other causes, as well.

Before we go any further, let us take a look at what a normal bowel movement looks like. Thereafter we will look at the causes of a green bowel movement, and when you should worry.

What Is a Normal Bowel Movement?

A "normal" bowel movement in adults can differ from person to person. To most people, it is one that is easy to pass. However, the Bristol Stool Chart, pictured below, describes an ideal stool as one that is brownish in color, soft, and shaped like a sausage.

The brown color of feces comes from bile. Bile is a green fluid produced by the liver, stored in the gallbladder, and released from there into the gastrointestinal tract to help in the digestion of fat.

As bile mixes with the contents of the gastrointestinal tract, bacteria in the large intestine act on it changing its color from green to yellow and then to brown. The rusty brown color of feces indicates that bile has been completely processed by the digestive system.

The Bristol stool chart showing the seven form scales

The Bristol stool chart showing the seven form scales

The Bristol Stool Chart helps you classify your stool into one of seven categories based on its shape and texture. In general, types 4 and 5 are normal. Type 4 is considered ideal because it is the easiest to pass.

To use this chart, all you need to do is point your physician to the category that best describes your stool. Your physician should then tell you whether or not you have a normal bowel movement.

The color of your stool is as important as its shape and texture. So let us take a quick look at the main causes of green bowel movement in adults.

What Causes of Green Bowel Movement?

Some of the reasons associated with green feces are totally harmless; others are not. There are four main reasons behind most green feces:

  • Eating excessive amounts of green vegetables, algae and grasses can make your stool green. Our digestive system will flush out the excess food with little to no change in color.
  • Green dyes are often used in foods such as ice cream, candies, popsicles, and gelatin. Eating these foods can stain your stool green. People have reported bright green stool a few hours after drinking green kool-aid.
  • There is a known correlation between the intake of certain supplements and the production of dark green stool. Spirulina, wheatgrass, barley grass, and chlorophyll are all supplements that contain chlorophyll—the green pigment in plants. Excess chlorophyll that your body can’t absorb will be expelled resulting in a green stool. Iron supplements are also known to cause dark green feces.
  • When material travels too fast through the large intestine, there is not enough time for bile to be broken down. Unprocessed bile will cause your stool to appear bright green. This is often associated with diarrhea.


Diarrhea increases bowel movement and hence decreases bowel transit time. Some conditions often accompanied by diarrhea include:

  • Celiac disease, also known as gluten intolerance
  • Irritable bowel syndrome (IBS)
  • Food poisoning
  • Use of laxatives
  • Side effects of a medication such as antibiotics
  • Bacteria overgrowth in the small bowel

Frequent diarrhea causes rapid loss of body fluids. When you are suffering from diarrhea, it is very important to make sure you are drinking adequate fluids to replace the fluid that is being lost.

Should You Worry About Green Stool?

A green bowel movement does not directly point to any disease if the shape and texture of your stool are normal. In this case, it is very likely due to a certain food you ate or a supplement you took.

Worried? Green BM may or may not be a sign of an underlying medical condition.

Worried? Green BM may or may not be a sign of an underlying medical condition.

The color of your stool should return to normal after the course of the supplement or after withdrawal from the suspected food. If it persists then talk to your physician to rule out the chance of any disease.

On the other hand, green bowel movement associated with mucus, loose stool or diarrhea is often an indication of an underlying medical condition. In this case, you should contact your physician and get evaluated immediately.

In general, a green bowel movement is considered normal if it is not persistent. However, it is a cause for concern if it is painful, strained, uncontrolled, or excessive. Take appropriate actions when your overall toilet experience deviates from normal. Keep tabs on your poop, stay safe, seek medical attention, and be healthy.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.


rmweller on October 17, 2018:

I never had green stools before 3 days ago. Some cramping no diet change. Lasted 2 days. Not sure what is going on. Would this be normal?

Glen Roberts on October 12, 2017:

I have a green film on hard stull is this bad . Im worried cause its been this way for about a month . Please help me

Sandra hall on June 24, 2017:

What type of health condition causes green stools

Venkatachari M from Hyderabad, India on April 16, 2017:

Very useful information. I was checking for green faeces and Darolac capsules. I was experiencing loose motions and got prescribed Darolac which caused green bowels now. It's a mix of 2,3,4 in your scale now.

KayBee on December 13, 2015:

You left out drinking red wine. I once had to pay a $610 lab fee because my ignorant doctor was concerned that I had green stool. I had told her that I drink red wine almost every night. She should have put two and two together. I did not even realize the cause until I switched to white wine. Ha!