Cancer Colon Cancer Causes & Risk Factors Advice About Bright Red Blood in Stool By Julie Wilkinson, BSN, RN Julie Wilkinson, BSN, RN LinkedIn Julie Wilkinson is a registered nurse and book author who has worked in both palliative care and critical care. Learn about our editorial process Updated on January 08, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Oliver Eng, MD Medically reviewed by Oliver Eng, MD Oliver Eng, MD, is a double board-certified surgeon and surgical oncologist and an Assistant Professor of Surgery at the University of Chicago. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Hemorrhoids Inflammatory Conditions Colon Polyps Constipation Bowel Infections Colon Cancer What to Do Diagnosis Frequently Asked Questions Blood is supposed to stay in your body. So seeing blood in your bowel movement can be frightening. Bloody stool is an indication that something is not working right, but it is not always a sign of colon cancer. Like the lining of your mouth or nose, the lining of the colon has lots of blood vessels, so any injury can lead to bright red rectal bleeding. A smear of blood on the toilet paper may be nothing to worry about, but don’t take a chance. Instead, ask your healthcare provider to help you discover the cause. This article explains the causes of bloody stool, when to call your healthcare provider, and what to expect at your healthcare visit. Verywell / Derek Abella Hemorrhoids Hemorrhoids are swollen blood vessels that can be inside or outside of the anus. They are a common, mostly harmless problem. However, they are fragile and can bleed, so they're the number one cause of bright red blood smears on the toilet paper. You may or may not feel any discomfort with a hemorrhoid. Pregnancy and straining during a bowel movement are two common causes of hemorrhoids. They are easily treatable and may even resolve on their own. What Are Hemorrhoids? Inflammatory Conditions Certain inflammatory diseases in the colon can cause bright red or dark red blood in the stools. These include: Inflammatory bowel disease (IBD) Crohn’s disease Ulcerative colitis Diverticular disease Treating Ulcerative Colitis: There Are More Options Than Ever Colon Polyps Colon polyps are growths on the inside wall of the colon. Most polyps are benign (non-cancerous) and do not cause any symptoms. Polyps can and do bleed, though, particularly larger ones. If your healthcare provider suspects a polyp, they will want to order a colonoscopy to investigate and remove the polyp. Untreated polyps can lead to colon cancer. Colorectal Cancer Screening The U.S. Preventive Services Task Force (USPSTF) recommends regular screening for colorectal cancer for adults who are 45 to 75 years old. Colon Polyps and Cancer Risk Constipation Constipation and straining to pass a large bowel movement can lead to smears of bright red blood on the toilet paper. Causes of constipation include: Not drinking enough waterLow-fiber dietsLack of exerciseChanges in routineEating too much dairyStressHolding your bowel movementsCertain medicationsCertain health conditionsPregnancy Let your healthcare provider know if you are straining to pass bowel movements. This straining can lead to tiny, uncomfortable tears in your anal tissues, called fissures. Anal sex can also sometimes cause these tiny fissures and rectal bleeding. Bowel Infections Untreated bowel infections, such as Escherichia coli (E. coli), can cause bloody diarrhea and abdominal pain. E. coli can stem from consuming undercooked meats or unpasteurized juice and dairy products. The infection requires antibiotic therapy. Colon Cancer Colon cancer can cause blood in the stool. However, in the early stages, most colon cancers do not generate any symptoms. Fecal testing can detect the presence of hidden blood in the stool. Stool DNA tests can look for the genetic material shed by polyps or tumors. If the visible blood in your stool is from colon cancer, it is most often from the left side of the colon (including the descending colon, sigmoid colon, or rectum). Cancer in the right side of the colon usually does not present with noticeable bleeding. What to Do About Blood in the Stool The best action you can take now is to pay attention to this symptom. If you're not positive about the cause, make an appointment with your healthcare provider. Prepare for your visit by asking yourself these questions: Was the blood in the stool, toilet bowl, or on the toilet paper?Was the blood bright red or dark red?Approximately how much blood did you see? (Keep in mind, a drop of blood in a toilet bowl will turn all of the water red.)Did you have to strain to pass the bowel movement?How frequently do you have bowel movements?Do you have other symptoms?When was your last colon cancer screening or colonoscopy?Do you have a history of polyps or a family history of polyps? When to Call a Healthcare Provider Contact your healthcare provider if you notice any of the following:Rectal bleeding that does not stopLarge amounts of bloodFoul-smelling stools with a coffee-grain appearance Diagnosis Your healthcare provider will complete a physical exam to look for any visible causes of rectal bleeding, like hemorrhoids or anal abrasion. They will also take your medical history. Then, they may order tests to investigate the cause further, even if it is obvious. Your healthcare provider might order: Complete blood count (CBC): This blood test can show how much blood you may have lost. Clotting time: If you take anticoagulants (blood thinners), your healthcare provider may want to check if your blood is too thin. Fecal occult blood test (FOBT) or fecal immunochemical test (FIT): These stool tests check for the presence of blood. Colonoscopy: In this procedure, a healthcare provider uses a scope to look inside the entire colon. This test allows the healthcare provider to see and remove any polyps in the colon lining. Sigmoidoscopy: This test is similar to a colonoscopy, but looks only at the lower part of the colon, including the sigmoid colon and the rectum. X-rays: Images of the lower intestinal tract may show any large abnormalities in the colon. Following the test(s), your healthcare provider will discuss the findings with you. They may potentially order further testing if imaging found abnormalities. Based on the results, they can develop a treatment plan, as needed. Summary Bloody stools can have many causes. Often, bleeding during a bowel movement is a clue to benign conditions, like hemorrhoids, constipation, or polyps. But sometimes, it can indicate something more serious such as an infection, intestinal disease, or cancer. A Word From Verywell Rectal bleeding is unsettling. If you notice bleeding when you have a bowel movement, rest assured that it is most likely due to something minor. Even so, it's essential to pay attention to the bleeding that occurs during a bowel movement. If your bowel habits change or you notice new bleeding, it's always best to get it checked out. Frequently Asked Questions What causes bright red blood in stool? Bright red blood in stool can be caused by hemorrhoids, inflammatory bowel disease (IBD), Crohn's disease, ulcerative colitis, diverticular disease, colon polyps, constipation, bowel infection, colon cancer, and gastrointestinal bleeding. Bright red blood usually indicates that the bleeding is coming from lower in the digestive tract. When should I be concerned about blood in my stool? Anytime you notice blood in your stool and aren't sure of the cause (such as an obvious hemorrhoid), you should contact a healthcare provider. Stool that is deep red, maroon, black, or tar-like can mean there is a substantial amount of blood in stool. How do I stop bloody stool? The best way to stop bloody stool is by treating its underlying cause. Bloody stool caused by a mild hemorrhoid may require little to no treatment since some hemorrhoids resolve themselves. Other causes warrant diagnosis and treatment by a healthcare provider. Are there foods that cause red stool? Yes, certain foods may cause stool to turn red, which can resemble blood. These include foods like red gelatin, popsicles, Gatorade, Kool-Aid, tomato juice or soup, beets, or any food that is made with natural or artificial red food coloring (red #40). Was this page helpful? Thanks for your feedback! Limiting processed foods and red meats can help ward off cancer risk. These recipes focus on antioxidant-rich foods to better protect you and your loved ones. Sign up and get your guide! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 9 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. American Society for Gastrointestinal Endoscopy. Understanding minor rectal bleeding. National Institute of Diabetes and Digestive and Kidney Diseases. Symptoms & causes of GI bleeding. Centers for Disease Control and Prevention. What should I know about screening?. Cleveland Clinic. Constipation. American Academy of Family Physicians. E coli infection. American Cancer Society. Colorectal cancer signs and symptoms. Johns Hopkins Medicine. Gastrointestinal bleeding or blood in the stool. Cleveland Clinic. Stool changes and what they mean. Cleveland Clinic. Rectal Bleeding. Additional Reading American Society for Gastrointestinal Endoscopy. Understanding minor rectal bleeding. Illinois Department of Public Health. Escherichia coli 0157: H7.