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What foods make stool green?


The color of a person’s stool can provide important information about their digestive health. Stool is usually brown due to the presence of bilirubin, a pigment produced when red blood cells break down. However, sometimes stool can appear green in color. Green stool is usually harmless, but identifying the underlying cause can help ensure there are no serious issues. In this article, we’ll explore some of the most common foods and drinks that can turn your stool green.

Bile and Digestion

Bile is a greenish-yellow fluid produced in the liver and concentrated in the gallbladder. During digestion, the gallbladder contracts and releases bile into the small intestine to help break down fats. Bile contains bilirubin, cholesterol, electrolytes, and various other compounds.

As bile travels through the digestive tract, bilirubin undergoes a chemical reaction that changes its color from green to brown. This reaction usually occurs rapidly enough that stool maintains a normal brown color. However, if food passes through the intestines quickly, bilirubin may not have time to turn brown. The result is green-colored stool.

Foods That Can Cause Green Stool

Leafy Greens

Consuming large quantities of leafy greens like spinach, kale, collard greens, and broccoli can lend a green hue to stool. These veggies are rich sources of the green plant pigment chlorophyll. Some of the chlorophyll is not fully broken down and gets excreted in feces.

High intakes of leafy greens are very healthy and these foods should not be avoided solely to prevent green stool. Just be aware that increasing your intake dramatically may briefly turn your stool green.

Green Food Coloring

Artificial green food dyes like FD&C Green No. 3 are sometimes used in processed foods and drinks. Food coloring passes through the digestive tract unchanged before getting excreted in stool. Large amounts of green dye can cause green stool.

So be aware of just how many artificially colored foods you consume, especially around holidays when decorated cookies and candies are abundant. Check labels and look for natural alternatives when possible.

Iron Supplements

Iron supplements are a very common cause of green stool. Iron in the supplements is not fully absorbed and the excess gets excreted. Iron excretion can vary based on the form of iron in the supplement and your own iron status.

If your stool only turns green after taking an iron supplement, it is likely the cause. You may need a lower dose or an alternative form like iron bisglycinate that is gentler on digestion.

Food Poisoning

Certain types of bacteria that cause food poisoning, like Salmonella and E. coli, can also turn stool green. Along with green diarrhea, symptoms of food poisoning include stomach cramps, fever, nausea and vomiting.

If you suspect you have food poisoning, seek medical care to test for bacterial contamination and receive IV fluids if dehydrated. Avoid suspected contaminated foods and thoroughly cook meats and eggs to prevent future illness.

Artificial Colors in Processed Foods

A variety of artificial food colors used in processed foods and drinks can tint the stool green. Yellow dyes like tartrazine or sunset yellow can mix with blue dyes like brilliant blue to create a green hue.

Check labels and avoid products with artificial colors, which provide no health benefit. Opt for more natural, minimally processed foods whenever you can.


Eating large amounts of black liquorice can also turn stool greenish or blue-green. This old-fashioned candy contains glycyrrhizin from liquorice root. Glycyrrhizin is metabolized into molecules that can discolor bile.

Enjoy liquorice treats in moderation. And look out for routine green stool if you suddenly overindulge in this candy.


Certain medications like antibiotics can sometimes contribute to green stool:

– Amoxicillin – Common penicillin antibiotic that can cause stool discoloration. Usually resolves after finishing the course.

– Iron supplements – As mentioned, unabsorbed iron gets excreted giving stool a greenish tint. Lower dose if persistent.

– Antacids containing aluminum hydroxide – Can turn stool pale green, gray or white. Usually not cause for concern.

– Anti-diarrheal medicines – Contain bismuth subsalicylate which may temporarily darken the stool.

If you notice green stool after starting a new medication, consult your pharmacist or doctor. They can recommend adjusting the dose or switching to an alternative.

When Green Stool May Indicate a Problem

In most instances, green stool is normal and not a cause for concern. However, there are some situations when it can signal an underlying issue:

Neon or Bright Green Stool

Stool that is an unusually bright or neon green color could indicate a bacterial infection or parasite. Certain strains of harmful bacteria like Pseudomonas aeruginosa can create stool with a very vibrant green color.

Parasites like Giardia may also cause bright green diarrhea, along with symptoms like nausea, bloating and fatigue. See a doctor right away if your stool is an abnormal green color. Stool testing can check for infection.

Persistent Green Stool

If you regularly notice green stool, get evaluated by a gastroenterologist. Chronic green stool can result from disorders that prevent bilirubin from turning stool brown. These include:

– Bile duct obstruction – Blocked bile ducts prevent bile from reaching the intestines. This requires urgent treatment.

– Bile deficiency – Liver damage or disease reduces bile production leading to less brown stool pigment.

– Fast transit time – Food passes rapidly through the intestines so bilirubin can’t be properly converted.

Testing like a stool sample analysis, abdominal ultrasound or CT scan can help diagnose the underlying cause of persistent green stool. Prompt treatment improves outcomes.

Other Symptoms

Keep an eye out for other digestive symptoms that accompany green stool:

– Diarrhea – Frequent passage of loose, watery stool. Can cause dehydration.

– Constipation – Difficulty passing hard, dry stool. May cause bloating and discomfort.

– Blood in stool – Bright red blood indicates lower GI bleeding like hemorrhoids or tears. Dark blood suggests upper GI bleeding.

– Abdominal pain – Stomach/intestine pain may signal blockage, infection or inflammatory conditions.

– Nausea and vomiting – Can accompany infections, blockages and other issues. Prevents proper digestion.

– Unintended weight loss – Losing weight without trying can result from poor nutrient absorption.

See a doctor promptly if green stool occurs alongside concerning symptoms like these. It may indicate a digestive problem in need of treatment.

When to See a Doctor

In most cases, green stool following a meal high in leafy greens, green food dye or iron supplements is not worrisome. Allow a day or two for stool color to return to normal. However, consult a doctor if you experience:

– Persistent or chronic green stool

– Neon or bright green stool

– Green stool accompanied by diarrhea, nausea or other concerning symptoms

– Stool that is white, clay-colored or very pale

– Recent illness or antibiotic use before stool color change

Describe any dietary factors that could explain green stool. The doctor can recommend appropriate testing based on your symptoms and health history. Prompt medical care helps diagnose any underlying condition.

Foods That Can Help Restore Normal Stool Color

Here are some healthy foods that can encourage brown stool color:

Food Effect on Stool Color
Beets Contain betalains that create red/purple pigments
Prunes Increase stool water content so bilirubin pigments dilute
Turmeric Contains curcumin that can turn stool yellow/brown
Apples Provide fiber to improve normal stool formation
Probiotics Support healthy gut flora for proper digestion

Focus on eating a balanced diet with plenty of fiber and water. This encourages regular bowel movements and allows bilirubin to be properly metabolized. The green color should fade within a day or two.

When to Seek Emergency Care

While green stool is typically harmless, some rare cases require prompt medical attention. Seek emergency care if you experience:

– Very dark green or black stool – Could indicate internal bleeding

– Red stool – Suggests bleeding in the lower intestines or rectum

– Yellowish stool – May be a sign of liver disease or bile duct obstruction

– No stool for 3 or more days – Signals a dangerous intestinal blockage

– High fever with abdominal pain – Can accompany severe infections

– Dizziness, rapid heart rate, confusion – Can result from dehydration due to severe diarrhea

Emergency room doctors can provide IV fluids and medications to stabilize dangerous conditions. They can also order stool studies, imaging tests and endoscopies to determine the underlying cause.

When Green Stool May Occur in Babies

Green stool is fairly common in newborns and infants. A baby’s immature digestive system can easily cause unprocessed bile to tint their poop green. Other common causes include:

– Breastfeeding – Early breast milk (colostrum) contains high levels of green-colored antibodies.

– Formula – Iron-fortified formulas will turn stool greenish or even greenish-black.

– Food sensitivities – Allergies to proteins in formula or breastmilk can cause green stool.

– Illness – Gastroenteritis and teething pain can cause green diarrhea.

If the baby is otherwise healthy, gaining weight, and has no diarrhea, green poop is not worrisome. But contact your pediatrician if it persists beyond one month of age or causes discomfort. Switching formulas or mom’s diet may help resolve the issue.

Preventing Green Stool

You can take some simple steps to help avoid green stool:

– Gradually increase high-chlorophyll foods – Don’t overload on greens all at once.

– Read ingredient labels – Watch for artificial food dyes, especially combinations of blue and yellow.

– Stay hydrated – Drink plenty of non-caffeinated fluids daily.

– Increase dietary fiber – Encourage normal bowel movements.

– Take iron supplements with food – Avoid taking on an empty stomach which worsens side effects.

– Check for food poisoning – Cook meats thoroughly and don’t leave foods sitting out.

– Avoid big changes in diet – Transition more slowly when increasing fiber, vegetables, etc.

– Consider probiotics – Healthy gut flora supports normal digestion and stool consistency.

Following a generally healthy diet and lifestyle can help maintain regular brown bowel movements. But the occasional green stool is usually harmless, especially if you know the cause.


In most cases, green stool is a temporary, harmless side effect of certain foods or medications. Leafy greens, iron supplements, and artificial food dyes are some of the top culprits. Stick to a balanced diet with adequate fiber and fluids to help encourage normal brown stool color. But when in doubt, consult your doctor – especially if green stool persists or you have worrisome symptoms. Addressing any underlying condition promptly leads to the best outcome. With the right medical guidance, green stool is usually nothing to worry about.