Dark green poop may be surprising or alarming upon your first encounter, but it actually has a very simple biological explanation and, as far as the brilliant rainbow of feces is concerned, is not normally a cause of significant concern.
Upon expulsion, poop is expected to be a light to medium shade of brown. This is partly the result of the dark green and yellowish-brown bile formed in the liver. Bile is secreted into the duodenum during digestion to help break down food particles alongside good bacteria.
The digestive process has an influence on the color of your feces, as do the types of foods you consume. Green and brown are common colors, but a change in the consistency as well as dark or bright green discoloration may indicate a medical crisis.
In This Article:
What Causes Green Stool?
Understanding why you have dark green feces first requires knowing why it’s normally brown in the first place.
Poop is a mix of undigested food, bile, bacteria, and dead blood cells. The brown coloration happens during the stool’s journey through the digestive tract where intestinal bacteria break down and feast on the leftover bile and other cell detritus it contains.
The underlying process is surprisingly complicated but the main takeaway here is that poop is normally greenish until exposure to intestinal bacteria, where turns it brown.
Now that the preliminaries are out of the way, let’s look at what dark green poop might mean.
Antibiotics, particularly the powerful ones that get prescribed for major infections, are capable of reducing the levels of bacteria in your intestinal tract.
As mentioned earlier, these are the same bacteria responsible for why poop normally appears brown and their loss means your feces can’t be processed as thoroughly during its trip through the body. Due to this, green stool is a known side effect of some antibiotics.
2. Vitamins and Supplements
The breakdown of vitamins and minerals within the GI tract can directly or indirectly affect the coloring of your poop. Colon-cleansing supplements such as senna, rhubarb, fiber, and cascara sagrada in particular may produce green poop.
Iron supplements and chlorophyll-containing supplements may also cause your stools to turn green temporarily. Wheatgrass, green tea, barley grass, and spirulina are all rich in the plant chemical that gives them their green hue. The resulting green waste is common due to their rapid breakdown in the digestion process.
A colon cleanse is a type of home treatment some individuals use to try and flush “toxins” from the body. Cleanses come in numerous varieties but typically employ some combination of supplements, enemas, and/or laxatives.
Since colon cleanses essentially force-evacuate your bowels, it’s possible for them to produce green stool by virtue of triggering a bowel movement prematurely, before feces has been properly processed.
It’s also possible to have dark green poop while pregnant. During pregnancy, a woman’s body produces more blood, and if she doesn’t get enough iron, she could become anemic. If that happens, she might then take iron supplements, a side effect of which is again black or green poop.
Iron supplements can cause other discomfort, such as constipation, so it may be in the best interest of pregnant women to increase their iron intake through diet, by consuming liver, red meat, and leafy greens.
5. Parasites, Viruses, and Bacteria
One of the first signs of an illness can be green poop. This discoloration may be caused by the Norwalk virus, E. coli, or salmonella, all of which cause a rapid breakdown of food and waste. Painful cramping, nausea, vomiting, and dizziness may be present.
Parasites and other harmful pathogens are usually contracted through the consumption of undercooked foods or contaminated water, hand-to-mouth contact with animals, traveling, and walking with bare feet.
6. Medical Procedures
Changes in the color of the stools can occur as a result of a medical procedure such as a bone marrow transplant, which may lead to graft versus host disease if the transplant is rejected.
Symptoms of the disease include intestinal problems like nausea and diarrhea, which may result in green feces.
Other procedures that may cause green poop include cesarean sections and other abdominal surgeries, or radiation treatment.
7. Bile Pigment
Bile pigments may affect the color of stool. Bile fluid has a yellowish-orange (bilirubin) or green (biliverdin) hue and is stored in the gallbladder after production by the liver. Its purpose is to help break down fats in the foods you eat.
Bile itself is broken down into waste to be excreted after passing through the intestine.
If there is a blockage or obstruction, the bile breakdown is impaired and there can be a green tint to the poop. Bile may also pass through the large colon at a rapid speed, causing an insufficient breakdown process and green poop.
Diseases Associated with Green Stool
1. Intestinal Disease-Related Causes of Green Stool
Several intestinal health conditions can cause green poop as a reaction to inflammation. These may include irritable bowel syndrome, intestinal cancer, celiac disease, and even eating disorders.
Less serious but still a cause for concern are issues such as the stomach flu and food poisoning, often caused by the parasites, viruses, or bacteria mentioned above, can also cause diarrhea that is green in color.
Having loose bowel movements more than three times over a 24-hour period is considered diarrhea. This occurs when food consumed passes through your digestive system rapidly. Green stool can be the result as green-colored bile is not properly broken down.
The diarrhea may also be present with mucus in the stool.
3. Anal Fissures
An anal fissure refers to a tear in the tissue within the anal canal or anus. This can be caused by trauma to the area and can be extremely painful. Tears or cuts may also be the result of inflammatory bowel disease, difficult bowel movements, or persistent diarrhea.
Anal fissures as a result of chronic diarrhea may cause green-colored stools.
What Foods Cause Green Stool?
1. Green Foods
Parents may remember the stringy green mess their precious baby would fill the diaper with after eating certain foods. Green poop can continue throughout life from foods containing chlorophyll.
These foods include but are not limited to kale, broccoli, spinach, watercress, bok choy, Swiss chard, beet greens, and arugula. Other chlorophyll-enriched plants are honeydew melons, pistachios, hemp seeds, and jalapenos. Many smoothies and juice drinks have the same effect.
2. Blue and Purple Foods
A combination of red and blue food dyes, purple dyes, and blue coloring on its own can cause green stool. These dyes are often used in wines, sodas, icing, processed fruit snacks, and drink mixes. The colors can also appear naturally in fruits like grapes and blueberries.
3. Coffee, Spicy Foods, and Alcohol
Certain beverages and foods, such as coffee, alcohol, and spicy foods, have a tendency to pass through the digestive system at a rapid pace. This is due to the laxative effect they have on the body.
The faster the digestion, the less time for breakdown of the bile, which may appear green in color. Green poop is often the result.
4. Special Diets
Special diets outlining a vegan, vegetarian, or other plant-based food plan are commonly high in chlorophyll-heavy foods. These result in green poop, as do most juice cleanses.
For some medical tests and procedures, special diets are required for optimal results. For example, a colonoscopy-prep diet may lead to the rapid digestion of any food you eat.
With high-fat diets, such as the keto diet, an excessive amount of bile is secreted by the liver. This may cause your body to expel green poop.
5. Green Food Dyes
Food dyes generally are not absorbed by the body and will get excreted along with other waste. If you have recently eaten a large number of foods that use green coloring (such as promotional St. Patrick’s Day treats), you may find yourself producing green stool over the following days.
How susceptible someone is to food coloring will vary from one individual to the next. It’s fully possible, for instance, for you and a friend to eat the same green-dyed foods but for only one of you to have a green poo as a result.
Green Poop Complications
Having green poop may be more than a nuisance, depending on the underlying cause. If the discoloration is due to certain blue, red, green, or purple foods you’ve consumed, it is a temporary situation.
If green poop is a persistent problem, immediate treatment may be necessary to avoid the potential complications of a medical condition.
Some conditions may cause loose bowel movements that lead to severe dehydration, abnormal potassium levels, and malnutrition. All of these may also relate to malabsorption syndrome.
Treating Dark Green Poop
Anyone can be affected by dark green poop; toddlers and adults alike. Treatment for dark green poop begins with identifying what the actual cause was.
Similarly, you should be able to remember whether or not you recently engaged in a colon cleanse (enemas are kind of hard to forget). If you suspect antibiotics or a nutritional supplement are involved, it’s best to consult with your doctor on how this can be determined. It’s strongly inadvisable to discontinue an antibiotic without your doctor’s approval since you were likely prescribed that medicine for a good reason.
Lastly, conditions such as food poisoning or irritable bowel syndrome come with other associated symptoms that can help identify them. In these instances, the green stool is likely accompanied by diarrhea, stomach cramps, nausea, vomiting, or other signs of digestive disagreement.
Tips To Treat Dark Green Stool at Home
- Over-enthusiastic eating of green foods or iron-rich items can be curtailed with simple diet adjustments, as can any indulgence in overly-dyed treats.
- Food poisoning requires bed rest, maintaining fluid intake, and easing in to bland foods once you’re able to keep them down. Most food poisoning cases resolve within a few days with or without treatment.
- Avoid giving yourself a colon cleanse.
- Avoid snacking, especially on refined grains and sugary foods. Healthy foods such as organic fruits and vegetables, protein, and healthy fats help maintain proper functioning of the gallbladder, liver, and digestive system.
- Promote bile production by adding fermented or sour foods to your meals. This can include one-fourth cup of kefir, kombucha, pickles, beet kvass, or sauerkraut; or enjoy grapefruit or lemon wedges. Drinking a glass of one teaspoon of raw apple cider vinegar and one-third cup of water with meals or just 30 minutes before meals may help.
- Consume a sufficient amount of fats to stimulate brain and cell tissue function. Fats also help maintain proper gallbladder function. Consume 12 grams of fat per meal by eating one tablespoon of butter, olive oil, or coconut oil; two tablespoons of sour cream or raw cream; one-third of an avocado; one ounce of cheddar cheese; or a handful of seeds or nuts.
- Use a combination of olive oil and citrus juice to boost bile production. Drink a glass of one-fourth cup of fresh lemon, orange, or grapefruit juice mixed with one tablespoon of organic olive oil every morning before breakfast or at bedtime. The same benefits can be enjoyed with a salad dressing made of one half cup of olive oil, one teaspoon of Dijon mustard, one-fourth cup of lemon juice, one crushed garlic clove, and a dash of sea salt.
When to See Your Doctor
A one-off incidence of green stool is rarely a cause for concern and can be safely ignored. If you find that you are having recurrent or repeat episodes of green bowel movements, however, a doctor’s appointment may be in order.
Often, an exam for green stool will involve some questions about any recent dietary or lifestyle changes that may be affecting digestion and the stool itself may get examined if nothing can be ruled out.
One important thing to keep in mind is that although most causes of green stool are benign, this does not stop green stool from occurring alongside other more problematic situations.
If your stool seems to have mucus or blood in it (bright red or tarry, almost black) or is very watery, medical attention may be advised. This also applies if you experience rectal pain, intermittent bouts of constipation, fever, or loss of appetite. These symptoms should always be paid attention to and investigated regardless of whether you have dark green poop or not.
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