What causes green poop? Related conditions and treatments

Overview: What does green poop look like?

In healthy people, poop color is determined by the color of the foods we eat and bile, which helps the body absorb fats. With good digestive health, stools are a brown or dark brown color. When stool color changes, it may be due to certain foods, problems with the digestive system, or bile issues. For instance, bright red or dark red stools indicate small or large intestine bleeding, which is bad. However, red stools can also mean someone has eaten red-colored food like beets. Black stools often indicate bleeding somewhere in the upper GI tract, like the stomach. However, eating black licorice or taking too many iron supplements can turn poop black. Pale or clay-colored stools usually mean a lack of bile in the small intestine, which usually indicates bile duct problems in the pancreas, liver, or gallbladder. It’s also a sign that people are drinking too much milk compared to other foods. So what do green or dark green stools mean? Green is an unusual color for feces, so green stools can be alarming, especially if they’re bright green. The good news is that green stools usually mean nothing unless other symptoms exist, such as diarrhea. When the only symptom is green poop in the toilet bowl, it’s usually due to eating too many vegetables or foods with green food coloring. 

What causes green poop?

Green poop is generally not a cause for worry. The digestive tract isn’t to blame. It’s usually caused by food.

The most common causes of green poop are:

• Green foods: When not properly digested, green foods can color the stools. 

• Green food coloring: Food dyes are not always absorbed by the body and can pass out of the body in the stools, giving stools a range of colors.

• Iron supplements: Taking iron supplements can turn the poop black or green. 

• Nursing: When infants first start nursing, their stools turn yellow-green. This should eventually transition to a yellow or light brown-yellow color in about three weeks.

• Diarrhea: Diarrhea often means that there is more bile acid in the stools, giving them a green pigment.

Foods likely to cause green poop include:

• Leafy greens full of chlorophyll, such as kale, wheatgrass, and broccoli

• Blueberries

• Green fruits

• Leafy herbs

• Matcha tea

• Pistachios

• Green-colored desserts like green cookies or green frosting

Diarrhea, or abnormally frequent bowel movements, is usually caused by food and other materials passing too quickly through the intestines. Normally, they would be reabsorbed and not pass through the stools. One of these substances is bile, an acid that sticks to fats so the small intestine can absorb them. Bile is yellow-green, about the same color as a light green olive. The intestines normally reabsorb it, so it doesn’t add any green pigment to normal stools. When people have diarrhea, much of the bile is not reabsorbed. It then shows up in the poop, giving it a green tint. 

Diarrhea is caused by a host of gastrointestinal conditions, including:

• Bacterial infections, such as Salmonella

• Viral infections, such as norovirus

• Parasite infections, such as Giardia

• Digestive system disorders

• Inflammatory bowel disease (IBD)

• Cancer

• Cancer treatments

• Irritable bowel syndrome (IBS)

• Food allergies

• Food intolerance, such as celiac disease

• Food poisoning

• Excess bile acid

• Medication side effects, especially antibiotics

Should I be worried about green poop?

Most green poop causes are not concerning. However, if green poop is accompanied by diarrhea that lasts for several days, then it is time to see a healthcare professional. If the diarrhea is watery or bloody, this is a serious symptom of the GI tract that requires immediate medical attention. Go to an emergency room if there are any signs of severe dehydration, such as excessive thirst, dry mouth, decreased urine output, dizziness, fatigue, or changes in mental status, such as confusion.

How is the cause of green poop diagnosed?

If the only problem is green poop, the clinician will try to find the possible cause, mostly through a medical history. The clinician will want to know when it started, what you eat, and whether there are other symptoms, such as diarrhea.

If diarrhea is present, the clinician will want to know when it started, what you eat, whether you’ve traveled, any medications being used, and any medical conditions you might have. He or she will start a physical exam by looking for signs of dehydration and may also order a stool test to identify any possible infection. 

If there are signs of a more serious problem, the clinician may refer you to a gastroenterologist, a specialist in the digestive health system. Further tests, such as blood tests, imaging, colonoscopy, or sigmoidoscopy, may be needed.

Is green poop contagious? 

If the only symptom is green poop, it’s not contagious. 

However, if there’s diarrhea along with green poop, infections that cause diarrhea can be contagious. People spread intestinal infections from their poop to other people’s mouths. The infecting pathogens are usually spread through unwashed hands and contaminated surfaces, objects, clothing, and food. 

To avoid spreading a diarrheal infection:

• Wash your hands after every bowel movement

• Wash your hands regularly during the day

• Use hand sanitizer during the day

• Prepare foods safely

• Avoid sharing objects like brushes or towels

• Avoid shaking people’s hands

How long does green poop last?

How long green poop lasts will depend on the cause, but don’t expect it to last more than a few days.

• Nursing infants will eventually produce yellowish stools about three weeks after their poop turns green.

• Green poop caused by diet or food dyes will resolve a day or two after the foods that cause it have been discontinued.

• Diarrhea-induced green poop will resolve when the diarrhea is treated, but treatment success will depend on the cause.

How to stop green poop

If the only problem is green poop, treatment is unnecessary. The causes are benign, so there’s usually no need for treatment.

For nursing infants, no treatment is necessary. The poop will eventually change to a yellowish or yellow-tan color over time.

No treatment is needed for green poop due to food or food dyes. If poop color is a worry, eliminating green food coloring and some leafy vegetables will usually bring back normal-colored stools.

Treatment of diarrhea will vary by cause. The first goal of treatment is to fix or prevent dehydration and any electrolyte imbalances. Depending on the cause, diarrhea is treated with over-the-counter medications, such as Pepto-Bismol (bismuth subsalicylate), prescription medications, and avoiding certain foods.

RELATED: Diarrhea treatments and medications

FAQs about the causes of green poop

What does it mean when your poop is green and your stomach hurts?

Abdominal pain and green poop usually point to a digestive system infection. An infection usually causes diarrhea. As a result, food moves too quickly through the digestive system. The yellow-green bile isn’t reabsorbed,so it passes into the stool. That’s what gives diarrhea stool a green pigment.

Does green poop mean pancreatitis?

Clay-colored stools are a possible sign of pancreatitis, but green poop is not. A swollen pancreas blocks the secretion of bile into the intestines. Without bile, stools appear pale, clay-colored, or even white. The bile that is supposed to go into the digestive system builds up in the body instead, so jaundice (yellow skin and eyes) is a common symptom of pancreatitis.

Can stress cause green poop?

Stress is not a cause of green poop. If the only symptom is green poop, chances are the culprit is something you ate. However, stress can worsen diarrhea, resulting in green stools because of the increased bile content in the stool.

What’s next? Additional resources for people with green poop

Test and diagnostics

• Acute diarrhea, American Family Physician

• Green stool, Mayo Clinic

• What causes diarrhea for a week with no other symptoms: diagnosis, prevention, and treatment, SingleCare

Treatments

• Diarrhea, StatPearls

• Diarrhea treatments and medications, SingleCare

Scientific studies and clinical trials

• Does stress induce bowel dysfunction?, Expert Review of Gastroenterology and Hepatology

More information on related health conditions

• Crohn’s disease treatments and medications, SingleCare

• Gluten intolerance symptoms: what are the early signs of gluten intolerance?, SingleCare

• IBS treatments and medications, SingleCare

• Ulcerative colitis treatments and medications, SingleCare

• What is lactose intolerance? Causes, symptoms, and treatments, SingleCare