“Black stool can reflect several things about your gut health,“Dr. Austin Garza, MD of Associates in Gastroenterology tells Parade. “It can be due to certain dietary pigments and medications, including iron supplements and bismuth-containing medications (e.g. Pepto Bismol). Black stool can also be an indicator of more serious conditions that cause internal bleeding.” In other words, aside from dark, tarry stool being weird, it can also be scary. You may be wondering if it’s normal, what it means, or if it’s a result of a food you ate. Plus, how do you know when to go to the doctor for what could potentially become a serious issue? Read on for answers to these questions and more.
Why is my poop black?
Poop can range in color and consistency and yes, there’s even a spectrum on which to judge poop. In fact, according to the Bristol Stool Scale, there are seven types of stool, which include:
Type 1: Separate hard lumps, like nuts (difficult to pass and can be black)Type 2: Sausage-shaped, but lumpyType 3: Like a sausage but with cracks on its surface (can be black)Type 4: Like a sausage or snake, smooth and soft (average stool)Type 5: Soft blobs with clear cut edgesType 6: Fluffy pieces with ragged edges, a mushy stool (diarrhea)Type 7: Watery, no solid pieces, entirely liquid (diarrhea)
Black stool is categorized as type 1 or type 3 on the Bristol Stool Scale. While healthy stool is usually type 4—smooth, soft, and generally easy to pass—stool can vary by a lot. So, what does black stool mean? If you are taking certain medications, as Dr. Garza mentioned above, such as iron supplements or medications with bismuth as an ingredient, your stool may appear black. Specific foods can also cause stool to be very dark. But if you’re not taking these medications and haven’t eaten anything known to cause black stool, it may be an indication of internal bleeding. According to Dr. Garza, black stool could potentially indicate stomach and duodenal ulcers—the latter of which, according to the Mayo Clinic, is a peptic ulcer that usually develops in the part of the small intestine called the duodenum. However, Irritable Bowel Syndrome (IBS) is usually not associated with black stool, despite this chronic condition causing similar symptoms of an internal bleed—cramping, abdominal pain, bloating, gas, diarrhea, and/or constipation. “Irritable Bowel Syndrome (IBS) is a common condition that includes abdominal pain, typically with either diarrhea, constipation, or a mix of both, but does not include black stool as a symptom,” Dr. Garza adds.
What does black poop mean?
Black poop can mean a few different things, but it’s always worth consulting your doctor about, whether or not you’re experiencing other symptoms. “Black and tarry stools are usually an indicator of an upper gastrointestinal bleed (GI bleed) that is occurring in the esophagus, stomach, and small intestine,” Dr. Jenna Liphart Rhoads, PhD., RN, and CNE advisor at NurseTogether.com explains. “The blood is black and tarry because it gets digested when passing through the rest of the GI system; a lower GI bleed (large intestine) would be bright red because the blood is not digested.” On its own black, tarry stools can be concerning but it’s also important to note if any symptoms accompany it. “Symptoms that accompany black stool that is concerning would include abdominal pain, light-headedness, and dizziness,” Dr. Garza explains. “These would all raise suspicion for internal bleeding.” Dr. Liphart Rhodes adds, “Other symptoms that may occur with a black/tarry stool include indigestion, stomach pain, nausea, diarrhea, weight loss, and stomach cramps.”
Is dark poop bad?
Most often, black poop is a sign of something going on in your GI tract. “Blackstool can be an indicator of bleeding in the gastrointestinal tract. This bleeding can originate from the oral cavity, esophagus, stomach, small intestine, or colon,” explains Dr. Cedrek McFadden, MD, FACS, FACRS, a board-certified colorectal surgeon. “It does not take much bleeding from these areas to create black or tarry stool, as little as 50 mL—or the amount of fluid in a shot glass.” On the more severe end of the spectrum, black stool can also be a potential sign of cancer. “Often, cancer causes these changes, which I then remove during surgery,” Dr. McFadden explains. “You may also be evaluated with an upper endoscopy and colonoscopy to ensure the stool color change is not coming from a bleeding ulcer, inflammation in the GI tract, or a tumor. "
What foods cause black or tarry stools?
In most cases, black or tarry stools is a cause of concern. However, if you’ve recently been eating a lot of foods known to discolor stools, that could also be the cause. “Foods that can cause black stool include beets, some fruits, and black licorice, as well as grape juice and red wine,” Dr. Garza explains.
When to go to the doctor for black poop
Black poop can be a cause for concern and it’s always best to consult a physician. Especially if you are experiencing additional symptoms such as abdominal pain, light-headedness, and dizziness with your abnormal stool, it’s worth bringing up to a doctor. “When present, symptoms may include a change in bowel habits (such as constipation or diarrhea), fatigue, weakness, abdominal pain, nausea, vomiting, or unexplained weight loss,” Dr. McFadden explains. “If you have black or tarry stool (with or without any of the other symptoms), you should go to the doctor. The doctor will review the use of any of the medications or foods that could cause the stools to be black.” Next up, these 10 important signs mean something’s not good for your mental health.
Sources
Dr. Austin Garza, MD of Associates in GastroenterologyDr. Jenna Liphart Rhoads, PhD., RN, and CNE advisor at NurseTogether.comDr. Cedrek McFadden, MD, FACS, FACRS, a board-certified colorectal surgeon.
