Noticing bloody or maroon-colored stool (poop) is alarming, and it may come on suddenly. The first step to determining the cause is thinking back on what you’ve recently had to eat.

Reasons for bloody or black, tarry stools range from recent dietary choices to more serious health conditions where a proper medical diagnosis and treatment may be necessary.

This article explores medical reasons that your stool may appear bloody and other causes of gastrointestinal bleeding. But remember, it’s always best to talk with a healthcare professional if you’re feeling concerned.

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Some foods have the ability to turn stool red. How, you ask? Because what goes in, must come out.

Stool mainly consists of three components (1):

  • water
  • bile (a digestive fluid released by the gallbladder)
  • undigested food components (carbohydrates, fats, proteins)

So if your diet includes large amounts of red foods, and that red pigment isn’t broken down all the way, that can change the color of poop.

“Foods that cause your stool to look bloody or tarry black include red beets, cranberries, blueberries, red food coloring, and processed foods that contain food coloring,” Johane M. Filemon, MS, RDN, CLT, a gut health and anti-inflammatory specialist, told Healthline.

In addition, partially undigested red foods may cause stools to look bloody.

The following foods may give stool a red appearance.

Beets

Beets get their rich, ruby color from betalains, a type of plant pigments or phytonutrients. Betalains belong to the anthocyanin family, and blueberries and cranberries contain them, too (2).

Betalains aren’t consistently digested or absorbed, and how well your body breaks them down can depend on several factors, including diet. There’s a good chance some of those pigment molecules make it to the end of the digestive tract relatively unchanged (2).

Acidity levels may influence the final color of the stool. In acidic environments, betalain appears to be a more vibrant red, while in alkaline (basic) environments, betalain appears as a blue or purple hue (2).

Overall, stool leans a little closer on the acidic side and, if beets do alter your stool, it tends to appear more pink, red, or maroon (2).

Beets can also change the color of your urine. This phenomenon is known as beeturia, and it’s estimated that 10–14% of people may experience it (3).

Jell-O and red food dye

Artificial dyes found in candies, sugary cereals, chips, and Jell-O can also dye poop. Red 40 is the most common red food dye in the United States (4).

Changes in stool color from these artificial colors or natural colors (like betalains or lycopene) should subside after a few days.

Tomatoes

Tomatoes get their color from a phytonutrient called lycopene, a member of the carotenoid family. Like betalain, the body’s ability to metabolize lycopene can vary, and the pigment can remain intact until it exits the body (5).

This amount of lycopene found in a tomato likely won’t change the color of stool, but drinking large amounts of tomato juice, enjoying a bowl of tomato soup, or eating heaps of fresh pico de gallo may be enough to turn stool red.

Watermelon is also high in lycopene and has the potential to turn stool red, according to an older study (6).

Red peppers

Red peppers, along with tomatoes and other fruits and vegetables, are fibrous.

Fiber resists digestion and instead feeds the good bacteria in the large intestine. So although fiber doesn’t get digested and absorbed like other foods, it’s still partially broken down before being passed (7).

However, anything that speeds up the digestion system means that there is less time to actually digest and break down food. Ironically, a diet high in insoluble fiber — the type of fiber found in red peppers and tomatoes — can have an almost laxative effect on the bowels (8).

So the especially fibrous skin of vegetables can sometimes appear in stool. Whether the skin of peppers is floating in the toilet or wrapped in the stool, it can be concerning to see that red color in the toilet bowl.

It’s not just peppers. This can happen with any colored fruit or vegetable. Kale and spinach are common culprits of green poop, for example.

Therefore, you may very well see fragments of tomato or red pepper skin in the toilet after a bowel movement (9).

Summary

Food dyes and certain components of other foods can turn stool red, making it appear bloody. For example, the plant compound that gives beets their color, betalain, may resist digestion and dye stool pinkish-red.

No foods should inherently cause bloody bowel movements. It may happen, but it’s probably not how you think, according to Filemon.

Spicy foods

Chili peppers always bring the heat, thanks to a compound called capsaicin.

Capsaicin is found in high amounts in hot peppers like red chili and spur or tabasco peppers. It interacts with pain receptors throughout the body and can create a burning sensation from your mouth to your bottom (10).

Capsaicin is also known for causing diarrhea in some people. Depending on the severity, it’s possible that blood can appear in the stool due to tears in the lining of the anus — an anal fissure. Excessive wiping after diarrhea may also lead to tears (10, 11).

This blood would appear bright red and may not appear in the stool itself but rather on the toilet paper or in the bowl. Wiping with a baby wipe may help provide relief, but will likely heal on its own, according to older research (11).

Otherwise, processed spicy foods, like chips, may also contain red food dye that could turn stool red. And if capsaicin from peppers does cause diarrhea, skin from those peppers could also appear in the stool.

Foodborne illness from red meat and poultry

Bloody diarrhea is a common symptom of food poisoning caused by eating tainted red meat or poultry. Salmonella, Escherichia coli (E. coli), Campylobacter, and listeria are common foodborne illnesses in the United States (12).

Some of these illnesses may resolve on their own, and the focus should be on symptom management. But medical treatment and antibiotic therapy may be needed in some cases (12).

Always make sure meat is cooked and stored at the proper temperatures to reduce the chance of food poisoning (13).

Summary

A compound in chili peppers called capsaicin may cause burning diarrhea, potentially initiating light rectal bleeding, while food poisoning from raw or undercooked meat can lead to diarrhea that may contain blood.

If food isn’t the offender, a health condition may be the root cause of bloody stools.

“With conditions such as ulcerative colitis, Crohn’s disease, and diverticulitis, certain foods can irritate the lining of the colon, and result in blood in your stool,” Filemon told Healthline.

“Not necessarily because there is anything wrong with that food, but because the already inflamed area [of the gut] is being aggravated more or your intolerance to said foods, which is also now causing a trigger in inflammation.”

Here are some conditions that have bloody stools as a symptom.

  • Hemorrhoids. Around 10 million people a year report having a hemorrhoid. Hemorrhoids are swollen veins around the anus. Most of the time, hemorrhoids heal on their own and are not serious conditions. While treatable, they can be painful and bleed during defecation. In this case, blood is usually bright red and either coats the stool or sprays across the toilet bowl (14).
  • Inflammatory bowel diseases, such as Crohn’s and ulcerative colitis. Recurring, bloody diarrhea is a main symptom of these inflammatory bowel diseases. Other symptoms include weight loss and abdominal pain. Talk with a doctor for proper diagnosis and for a personalized treatment plan if you’re concerned that you may have one of these conditions (15).
  • Diverticulitis. Diverticula are inflamed pouches in the color. During a bout of diverticulitis, severe abdominal pain may be accompanied by a large number of red or maroon bowel movements that come on suddenly. High fat foods and red meat are associated with a higher risk (16).
  • Polyps or cancer. Rectal bleeding with dark-brown or black stools may be a sign of polyps or colon cancer. Other symptoms include weight loss, changes in bowel habits, or narrowing of stool. The American Cancer Society recommends that people at average risk of developing colon cancer start regular screening at 45 years of age (17, 18).
Summary

Rectal bleeding may be a sign of medical condition, whether mild — like most cases of hemorrhoids — or serious, such as colon cancer. If you’re experiencing blood in your stool, it’s important to talk with a healthcare professional for diagnosis and care.

If you’ve determined that red, maroon, or black, tarry stools aren’t due to eating too many of your favorite red foods, then it’s probably time to call a doctor.

“You should seek medical attention as soon as you can with a new symptom such as blood in your stool where you’ve never received a diagnosis and do not know the cause, especially if it is accompanied with other symptoms, such as fever or vomiting,” Filemon said.

Summary

Talk with a healthcare professional if you have bloody stool, especially if you don’t have a diagnosis. A doctor can help with symptom management, prescribe any needed medications, and detect serious conditions like cancer.

Bloody poop from food itself is generally only possible during active bouts of food poisoning.

Otherwise, red foods like beets, Jell-O, or tomatoes contain pigments that can dye stool red or remain partially undigested in the bowel movement. They may cause your stool to appear as though it contains blood.

Several medical conditions, including hemorrhoids, Crohn’s disease, ulcerative colitis, and polyps in the colon, can cause bloody stool or bloody diarrhea.

Many conditions will also have accompanying symptoms like severe abdominal pain and dizziness. It’s best to talk with a doctor if you experience bloody stools in conjunction with symptoms like these, especially if you don’t have a diagnosis.

Just one thing

Try this today: You can stay connected with Johane M. Filemon, MS, RDN, CLT, on Instagram or visit her website here.