Why is my poop green? Stool colors explained
A common stool color change, green poop can mean that you’ve been eating green vegetables (which are rich in chlorophyll) or green, blue, or purple food coloring, or it can be caused by any condition that leads to diarrhea or loose stools.Although stool is normally brown, the occasional green stool can fall within the normal range of stool colors. See your doctor if green stool (or another unusual stool color) is ongoing or if you have other symptoms, like fever, diarrhea, nausea, vomiting, or pain.Here are eight possible causes of green poop (whether it is dark, bright, light green, or floating).
Green poop can simply result from consuming meals with green vegetables, like spinach, kale, broccoli, Swiss chard, bok choy, beet greens, arugula, and watercress. It doesn’t mean there’s something wrong. Dark green, leafy vegetables are rich in chlorophyll, the pigment that gives plants their color.
A small serving may not be enough to turn your stool green, but it may be an issue if you’re having larger servings, such as those found in smoothies, juices, pureed soups, large salads, guacamole, or a combination of different chlorophyll-rich foods. Matcha, a type of powdered green tea, can also make stools a bright green hue.Some foods contain green (or blue and yellow) food coloring that may turn your poop green. These dyes are sometimes used in canned green peas, green beer, breakfast cereal, candy, jarred pickles, salad dressing, beverages, cake and cookie icing, and desserts. You’ll also see these dyes in food around St. Patrick’s Day and Christmas.
Blue and Purple Foods
Besides the obvious green foods, deep blue or purple foods can sometimes lead to green poop. Blueberries, grapes, and red wine, for instance, can result in a dark green-blue stool. Purple (or red and blue) food coloring in drink mixes, grape Kool-Aid and soda, frozen ice pops, cake icing, blue Gatorade, packaged fruit snacks, licorice, and grape-flavored Pedialyte can also cause dark or bright green poop. These food dye colors are often used during holidays such as Easter, Independence Day, and Halloween.
Coffee, Spicy Foods, and Alcohol
As bile makes its way through the small intestine to the large intestine via the bile ducts, it progressively changes color from green to yellow to brown. This is due to the action of bacteria in the large intestine acting on bile salts.
In some cases, consuming lots of coffee, jalapenos, chili pepper, and alcohol can have a laxative effect, causing foods to pass through the intestines faster than normal (called decreased transit time) and before stool change color from green to brown.
Vitamins, Supplements, and Medication
Taking iron supplements can change the color of your poop to dark green (or black). Other vitamins, supplements, and teas that can lead to green poop include:
- Senna, cascara sagrada, rhubarb, fiber supplements, and other laxatives.
- Nutritional supplements that contain chlorophyll, such as greens powder, green tea, wheatgrass, spirulina, barley grass, chlorella, blue-green algae, and chlorophyll.
- Yerba mate tea
- Medication that can cause loose stools or diarrhea as a side effect, such as metformin, Lexapro (escitalopram), Nyquil, Zoloft (sertraline), or antibiotics like ciprofloxacin.
Whether you’re eating a generally healthy diet or are on a vegetarian or vegan diet, consuming plenty of chlorophyll-rich green vegetables and fruits can make your poop green. Juicing or going on a juice cleanse will also up your intake of chlorophyll and, in turn, increase the likelihood of green-tinged stools.
If you experience green stools during a colon cleanse, it may be due to food rushing through your intestines too quickly to allow bacteria to give your stool its characteristic brown color.A high-fat diet, like the keto diet, may give your poop a bright green hue. With a high-fat intake, your body produces more bile to digest these fats and excess green-colored bile may find its way into the toilet bowl.
Green stool can occur during pregnancy. Some women get it in the earliest weeks of their pregnancy, sometimes even before the BFP (“big fat positive”) on the pregnancy test. Other women get it because they take prenatal vitamins (which contain a higher dose of iron than the typical multivitamin) or iron supplements.Green stool can also happen during the third trimester. Some women get loose green stools during late pregnancy as food moves rapidly through the intestines.
Green Poop in Babies, Toddlers, and Older Kids
An infant’s first bowel movements are typically green-black in color. Known as “meconium“, you usually don’t see it after an infant is three days old.
Dark green (or green black) poop in babies may be caused by iron supplements and iron-enriched foods, such as baby formula. If your baby’s poop appears black or dark, it’s a good idea to check with your pediatrician.If a breastfed baby has green poop, it could be something in the mother’s diet, like green vegetables or food made with green or purple food coloring. In some cases, it may be a sensitivity or allergy to something in the mother’s or baby’s diet.Green poop in breastfed babies (particularly “EBF” or exclusively breastfed babies) could also be a sign that the baby is getting too much low-calorie, low-fat foremilk (the milk that comes first in a feeding) and not enough hindmilk, which is higher in fat. It could mean that the baby isn’t feeding long enough on each breast or draining the breast effectively or that there is an oversupply of breast milk. A lactation consultant may be able to help identify the issue.
Kids often eat foods that contain food dyes, including green, purple, blue and yellow, or red and blue coloring. They are found in grape Pedialyte and some kids’ breakfast cereals, beverages, candies, birthday cakes, and cookies. Chewing on green or purple crayons can also change the color of stools.
Conditions That Can Cause Green Stool
Diarrhea decreases bowel transit time, so any condition that causes diarrhea can result in a green stool, including:
- Food poisoning
- Infectious or traveler’s diarrhea (especially Salmonella, E.coli, and Giardia). Bacterial, parasitic, and viral intestinal infections can cause your intestines to flush faster than normal.
- Antibiotic-associated diarrhea (also known as pseudomembranous colitis)
- Lactose intolerance
- Premenstrual syndrome (PMS)
- Celiac disease
- Ulcerative colitis
- Crohn’s disease
- Irritable bowel syndrome (IBS)
- Eating disorders that involve laxative abuse
- After surgery, such as a cesarean section (also known as a C-section)
- Graft versus host disease. A condition that can develop after surgery for a bone marrow transplant.
When to See Your Doctor
It’s important to talk to your doctor if your green stools are ongoing and/or accompanied by fever, stomach aches or pain, blood in the stool (or black stool), watery or liquid stool, or other symptoms. A rare but serious cause of green stool in kids and adults is poisoning by chemicals such as the pesticide paraquat.