Why Is My Poop Green? Causes & When It’s Serious

Key takeaways:

• Green poop can be harmless and is often caused by your diet, certain supplements, or medications.
• If green stools continue, this may mean you have a digestive issue, especially when the green poop is accompanied by other symptoms.
• Knowing when you should see a doctor will help you to identify any problems and make sure they are treated quickly.

Seeing green poop after you have gone to the toilet can be a bit surprising, especially if it happens more than once. Green poop can result from various causes, including what you eat, some medications, and also by things that are happening within your digestive system.

While green poop is most often harmless, you should know when this might mean you should get medical attention. Let’s go over some common causes of green poop, ways to manage green poop at home, and then look at some signs that suggest it may be time to consult your doctor.

Is green poop normal?

Sometimes green poop can be entirely normal, especially if you have had recent changes in your diet, supplement intake, or medication changes.

In most cases, green poop goes away on its own. If your green poop is ongoing or it appears along with other symptoms like stomach pain, nausea, vomiting, or diarrhea, it could mean you have an underlying digestive problem that needs medical attention.

Causes of green poop

Your dietary choices, bile pigmentation, supplements you ingest, and medications you take can cause green poop.

Dietary choices

Many foods can give your poop a green color, especially foods that are high in the pigment chlorophyll or artificial green dyes. Examples include:

• Leafy greens: Eating large quantities of dark leafy greens such as spinach, kale, collards, and turnip greens can turn your poop green.
• Foods with green food coloring: Many processed foods, such as cake frostings and candies, use green food coloring. These can sometimes cause your poop to turn green, especially if eaten in large amounts.
• Green smoothies or juices: Drinking green smoothies that incorporate leafy greens such as spinach, kale, and watercress can turn your poop green. Spirulina, a type of blue-green algae that has become popular as an ingredient in smoothies, can also cause your poop to look green.

Green poop usually returns to its normal color within a day or two after the food has had time to be digested and expelled.

Bile pigmentation

Bile is a digestive fluid produced by your liver and stored in your gallbladder. It helps your body to digest fats and is released into the upper part of your small intestine as it is needed. The color of bile starts as green but gradually turns brown as it moves through your intestines.

If your poop passes very quickly through your intestines because you have diarrhea or you are eating a diet high in fiber, your poop may look green because the bile has not had enough time to be processed. This color change is generally harmless unless it continues or you have persistent diarrhea or other symptoms such as vomiting or stomach pain.

Iron supplements

Iron supplements, whether they have been prescribed for you or you are getting them over the counter, can darken your stool color, sometimes giving your poop a greenish or even black appearance.

This discoloration is generally harmless. However, if you have other symptoms such as nausea, vomiting, or stomach pain, you should consult with your healthcare provider.

Medications and laxatives

Certain medications, especially antibiotics, can cause changes in the color of your poop because they often disrupt the normal balance of good bacteria in your gut.

Laxatives can also speed up the passage of material through your intestines, making your poop appear green, as the greenish bile produced by your liver doesn’t fully break down. If you are taking medications, and you consistently have green poop, it’s best to consult your healthcare provider for advice.

What green poop may mean based on appearance, consistency, or another symptom or condition

Here are some more specific causes and meanings behind green stool, based on its appearance, consistency, and any additional symptoms you may be experiencing.

Dark or blackish-green poop

If you are taking an iron supplement or a multivitamin with iron, you may see dark or blackish-green poop. This can also happen if you are eating a diet high in leafy greens such as collards, kale, or spinach that contain the green pigment chlorophyll.

Dark green poop or poop that is blackish green is usually harmless but if you are having other symptoms such as nausea, vomiting, or stomach pain, you should see your healthcare provider.

Bright green poop

Poop that is bright green is often from eating foods that contain artificial green food coloring. Or, it can be from bile passing quickly through your intestines.

Your poop should return to normal once the food is no longer being eaten or the cause for the quick passage of stool through your intestines is no longer present.

Hard green poop

If you are taking an iron supplement or multivitamin containing iron, you may experience constipation along with green-colored poop.

Constipation combined with green stool may result from iron supplements as well as from eating a very high-fiber diet. Increasing your intake of water and lowering the total fiber intake from your diet can often help.

Loose green poop

Green diarrhea can often occur if you have a gastrointestinal upset or you have a rapid passage of material through your intestines, as seen in conditions like IBS or food poisoning. If you have persistent diarrhea with green poop, you should be seen by your doctor.

Green poop with mucus

Most often, the presence of mucus means inflammation, as it is your body’s way of trying to soothe and heal the inflamed area.

Green poop filled with mucus may mean you have an infection or inflammation in your digestive tract. The combination of green poop and mucus is a sign you need to see your physician, especially if it continues for more than a day or two, or if you have other symptoms.

Green poop with stomach pain

If you are having green poop along with stomach pain, you may have an intestinal bacterial infection such as salmonella or giardia, or viral gastroenteritis.

If these symptoms continue for more than a day or so, especially if you are having other symptoms such as vomiting or fever, you should see your physician.

Green poop while breastfeeding

If you have recently had a baby and are breastfeeding, it’s not uncommon for your baby to have greenish poop.

This can also sometimes be seen in babies who are fed formula. As long as the baby is healthy and feeding well, green poop in your baby is generally not a concern. However, if you are having green poop while breastfeeding, it’s unlikely that breastfeeding is the cause. Please see the other reasons for green poop discussed in this article.

Green poop while pregnant

If you are pregnant, you might have green poop because you are taking prenatal vitamins that are high in iron.

Green poop could also be caused by changes in your diet, such as consuming large amounts of green leafy vegetables, such as kale or spinach. If you are having other symptoms along with the green poop, such as stomach pain or vomiting, you should be seen by your doctor.

Green poop after drinking alcohol

If you have green poop after drinking alcohol, it could mean the alcohol has interfered with your digestive process. Alcohol is a well-known intestinal irritant, and you can experience diarrhea after drinking as your body’s way to expel that irritant as quickly as possible.

Bile, a greenish-colored digestive fluid made by your liver and released into your intestines from your gallbladder, usually changes from a green to a brown color before you expel it in your stool. But when your digestive process speeds up after drinking, the bile can remain green, as it has not had enough time to turn its normal brown color. Excessive alcohol intake can also lead to diarrhea, which speeds up your digestion, causing green poop.

Read our guides on different types of stool and stool colors for more.

When to see a doctor about green poop

If you are having green poop, there are times when seeing your physician is the best course of action, especially if you are also experiencing other symptoms.

You should see your doctor if:

• You have diarrhea that lasts longer than a few days.
• You experience severe stomach pain or abdominal cramping.
• You notice you have lost weight but are not trying to and are not on a diet.
• You have nausea or vomiting.

You should go to the emergency room if:

• You see blood in your poop, which could appear dark red or black.
• You start to become dehydrated and are experiencing symptoms such as dizziness, a fast heartbeat, or mental contusion.
• You develop a high fever, have severe abdominal pain, or rapid pulse, all of which may be signs of an infection.

Questions to ask your doctor about green poop

To better understand the causes of and treatments for green stool, consider asking your doctor these questions.

• Could what I am eating, my supplements, or my medications be causing green poop?
• Are there any tests you would advise me to have to determine the cause of my green poop?
• Should I change my diet or my medications to get rid of green poop?
• What other symptoms should I look for if the green poop continues?

How to stop or treat green poop

Consider these steps to help manage or reduce green stool.

Make changes to your diet

If you believe what you are eating may be causing you to have green poop, limiting or stopping foods with artificial dyes or those high in chlorophyll such as large amounts of leafy greens can help.

Review your supplements and medications

If you’re taking iron, a multivitamin containing iron, or other supplements that might be changing the color of your poop, talk with your healthcare provider about possible adjustments. Your physician may suggest different iron or supplement formulations or perhaps advise a different medication dosing strategy.

Support your digestive health

Eating a balanced diet rich in fiber, lean proteins, and a variety of fruits and vegetables can aid in supporting healthy digestion, which can help to normalize your stool color over time. If a course of antibiotics is the cause of your green poop, taking a probiotic may help to restore your normal gut bacteria.

How to prevent green poop

To keep your digestive system healthy and avoid green stool, consider these preventive steps.

Eat a balanced diet

A balanced diet rich in lean protein, a variety of vegetables and fruits, and without excessive dyes or processed foods can help prevent green poop. Aim for a diet rich in natural colors from fruits and vegetables and avoid foods with artificial colors.

Get adequate hydration

Drinking plenty of water to stay hydrated is crucial for your digestive health. Drinking enough water helps improve your digestion and allows the bile produced by your liver to break down fully, which can prevent green poop.

Keep up with routine health check-ups

Regular check-ups allow you to discuss any unusual symptoms with your healthcare provider. Catching changes early will help you address potential problems and keep your digestion on track. This is especially important if you have a chronic digestive condition such as irritable bowel syndrome (IBS) or Crohn’s disease.

Frequently asked questions: green poop

Here are answers to common questions about green stool to help you understand when it may be a concern.

Is green poop a sign of cancer?

While green poop alone is not a typical sign of cancer, if you are constantly experiencing green poop along with other symptoms like stomach pain or unexplained weight loss, you should be seen by your physician to be sure you don’t have a serious condition.

Can pancreas problems cause green poop?

Pancreatic issues can affect your digestion, but green stool is not a common symptom with pancreas problems. Pancreatic issues usually cause pale or fatty appearing stools. If you are constantly having green poop along with other symptoms such as stomach pain, you should see your healthcare provider to discuss your symptoms.

Is green poop caused by a liver problem?

Liver problems usually cause pale or clay-colored poop, not green. Any unexplained change in your stool color should be discussed with your healthcare provider.

Managing green poop

Green poop is often harmless and can be due to your diet, medications, or supplements. If you frequently experience green poop or are having additional symptoms such as stomach pain, nausea, or vomiting, you should consult with your healthcare provider. Being proactive about your digestive health by getting regular checkups, eating a healthy well-balanced diet, and drinking plenty of fluids can help to prevent episodes of green poop in the future.

General Medicine follows a strict editorial process, including using real experts to write our articles, vetted primary sources, fact-checking, a secondary medical review, and updates as necessary. This article was medically reviewed and fact checked by Dr. Pallabi Sanyal-Dey, MD.

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