Red stool usually means one of two things: you ate something red, or there’s bleeding somewhere in your lower digestive tract. Most of the time, the cause is minor and treatable. But the color, consistency, and any accompanying symptoms all matter when figuring out what’s going on.
Foods and Substances That Turn Stool Red
Before assuming the worst, consider what you’ve eaten in the past 48 hours. Beets are the most common culprit. They contain pigments that survive digestion and can turn both stool and urine a startling shade of pink or red. Dragon fruit, blackberries, rhubarb, tomato soup, red velvet cake, and anything with red food dye (like fruit punch, popsicles, or red licorice) can do the same thing.
If you ate any of these recently and feel perfectly fine otherwise, the red color is almost certainly harmless and will clear within a day or two. The simple test: stop eating the suspect food and see if your stool returns to normal.
What Bright Red Blood Actually Looks Like
Blood in stool looks different from food coloring. It may appear as streaks on the surface of your stool, drops in the toilet bowl, or blood on the toilet paper when you wipe. Sometimes it mixes into the stool itself, giving it a uniformly reddish or maroon appearance. The color tells you roughly where the bleeding is coming from.
Bright red blood typically originates low in the digestive tract: the colon, rectum, or anus. Maroon-colored stool can also come from lower in the intestines, but occasionally signals rapid, high-volume bleeding from higher up, such as a stomach ulcer where blood moves through so quickly it doesn’t have time to darken. Black, tarry stool is a different situation entirely. It usually means bleeding in the esophagus, stomach, or small intestine, where blood has been partially digested on its way through.
Hemorrhoids and Anal Fissures
Hemorrhoids are the single most common cause of blood in stool. These are swollen veins in the rectum or anus, and they often develop from straining during bowel movements, sitting for long periods, or chronic constipation. The blood is usually bright red and appears on the toilet paper or drips into the bowl. Hemorrhoids can be uncomfortable, but they’re rarely dangerous.
Anal fissures are small tears in the lining of the anal canal, also frequently caused by straining or passing hard stool. They tend to cause a sharp, stinging pain during bowel movements along with bright red bleeding. Most fissures heal on their own within a few weeks with increased fiber and water intake to soften stool.
Inflammatory Bowel Disease
Ulcerative colitis and Crohn’s disease both cause chronic inflammation in the digestive tract that can lead to recurring bloody stool. Ulcerative colitis specifically targets the lining of the large intestine and rectum, creating ulcers that bleed when stool passes over them.
In its mildest form, called ulcerative proctitis, the inflammation stays confined to the rectum and rectal bleeding may be the only noticeable symptom. As the disease extends further into the colon, it can cause bloody diarrhea, abdominal cramping, an urgent need to use the bathroom, fatigue, and weight loss. Crohn’s disease more commonly affects the small intestine but can also involve the colon and cause visible bleeding. Both conditions are chronic but manageable with treatment, and they tend to cycle between flare-ups and periods of remission.
Diverticulitis and Colon Polyps
Diverticulitis occurs when small pouches that form in the colon wall become infected and inflamed. The inflammation weakens nearby blood vessels, which can rupture and cause sudden, sometimes heavy, painless bleeding. This is more common in people over 40 and is often associated with a low-fiber diet.
Colon polyps are small growths on the inner lining of the colon. Most are harmless, but some can develop into colorectal cancer over time. Both polyps and cancerous growths can bleed when stool rubs against them, producing red or maroon-colored blood. Among people 45 and older who report a new episode of rectal bleeding, roughly 2 to 7 percent are eventually diagnosed with colorectal cancer. That means the vast majority have a benign cause, but it’s also common enough that screening matters. The U.S. Preventive Services Task Force recommends colorectal cancer screening for all adults between ages 45 and 75.
Medications That Change Stool Color
Certain medications can make stool appear red or reddish-orange without any bleeding involved. Blood thinners and anti-clotting medications can also cause actual bleeding by making it harder for your body to stop small bleeds in the digestive tract. If you’ve recently started a new medication and notice a color change, check the side effect information before panicking, but mention it to your doctor at your next visit.
Red Stool in Babies and Young Children
Red stool in infants has its own set of causes. Anal fissures are common in babies, especially those dealing with constipation. Another possibility is cow’s milk protein allergy, which can cause loose or bloody stools even in breastfed infants (if the nursing parent consumes dairy). In its milder form, a baby may have flecks of blood in an otherwise normal stool with no other symptoms. This condition, sometimes called cow’s milk protein enterocolitis, is typically outgrown and resolves when dairy is removed from the diet.
Certain infant medications can also discolor stool. One common antibiotic can interact with the iron in baby formula to produce reddish-colored stool that looks alarming but is harmless.
Signs That Need Immediate Attention
A small amount of bright red blood on toilet paper after a hard bowel movement, with no other symptoms, is usually not an emergency. But certain combinations of symptoms signal something more serious. Heavy or continuous bleeding, severe abdominal pain or cramping paired with bleeding, and any signs that your body is losing too much blood all warrant a trip to the emergency room.
Those signs of significant blood loss include dizziness or lightheadedness when you stand up, rapid shallow breathing, blurred vision, fainting, confusion, nausea, cold or clammy skin, and very low urine output. These symptoms suggest the bleeding is fast enough to affect your blood pressure and circulation.
Even without emergency symptoms, rectal bleeding that recurs over days or weeks, changes in bowel habits that persist, or unexplained weight loss alongside bloody stool are all worth getting evaluated. A single episode tied to constipation or a known food is one thing. A pattern is something different.