Key takeaways:
Stringy or fibrous poop happens to almost everyone at some point in their life. It’s not necessarily something to worry about unless you’re having other symptoms pointing to something more serious.
Fiber strings in your poop are usually just undigested fiber. Stringy, thin stools are something a little different, and a few different medical conditions can cause it.
Changes in the appearance of your poop can be normal. But you should talk with your primary care provider if you’re also experiencing things like change in appetite, weight loss, or blood in your stool.
Many people make a habit of checking what their poop looks like. So if you peek in the toilet after a bowel movement, you aren’t alone. In fact, there’s a good reason to do this. Changes in your poop can give you information about your digestion. It can even be a sign of certain medical conditions. Here we discuss the causes of fibrous, ribbon-like, or stringy poop, and when it might mean there’s something else going on.
What do fiber strings in your poop look like?
Fiber strings look like undigested food in your poop. These fiber strings are often white in appearance and can look similar to threads. For example, if you eat a lot of bananas, you may notice stringy black lines in your poop. These are from the center of the banana. And sometimes fiber strings look like straws of undigested food — like a long, thin piece of carrot, for example.
But here’s where things can get a little tricky. Depending on who you ask, stringy poop can mean different things. They might be referring to long, narrow poops. This is also sometimes called shoestring poop, because of how long and thin it is. And this is different than just seeing stringy fiber in your poop. So in the next section, we go through a list of what can cause this.
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What causes stringy poop?
Fiber strings in your poop come from partially digested fiber from the food you eat. This is because fiber is hard to digest — just one of the reasons fiber is so good for your gut health.
Long, narrow, stringy poop has a few more causes. And since some of these can be a little more serious, we go through them in more detail below.
Changes in your routine
Certain disruptions in your usual schedule may also have an effect on what your poop looks like. For example, if you’re traveling, you may not be going to the bathroom as often. Or if you’re less physically active, you may be pooping less, and your poop may look narrower than usual.
How much water you drink
Drinking water can help push your poop out of your body, making it less likely for you to become constipated. If you have a few days when you’re drinking less water than you normally do, you may notice that your poop looks thinner than usual.
Medical conditions
Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) disorder that leads to changes in a person’s poop. Sometimes, IBS can cause mucus in the stool. This can give poop a stringy appearance. Other GI disorders like Crohn’s disease and ulcerative colitis may also cause bloody mucus in a person’s poop, giving it a stringy appearance.
Infections
Certain infections caused by bacteria or parasites can lead to diarrhea, causing poop to look stringy. And some viruses can also cause loose stools — think of your typical 24-hour stomach bug that has you repeatedly visiting the toilet. Any of these types of infections is likely to cause more than stringy-looking poop. In these cases, you’ll probably have symptoms like fever, nausea, vomiting, and stomach cramps.
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Colorectal cancer
In rare cases, colorectal cancer can also cause poop that appears narrower. But this is a less common cause of shoestring poop. And thin poop alone is usually not a reason to worry about colorectal cancer. Rather, a person with colorectal cancer may experience narrow stools as well as bleeding from the rectum, weight loss, and noticeable changes in their poop that don’t go away after a few days.
Other medical conditions
Other reasons that a person may have narrower poop than usual are rare but include:
Polyps in your colon: Sometimes a person can have small growths or polyps in their colon. Most often, they aren’t dangerous. They may lead to changes in poop, including thin-looking stool.
Bowel obstruction: A bowel obstruction is a blockage in the intestine. This can be caused by things like scar tissue from past surgery, infections, and even severe constipation. Along with a noticeable decrease in bowel movements, this also causes pretty intense stomach pain.
Fecal impaction: When a person’s poop builds up in their rectum, it can cause what’s known as a fecal impaction. In this case, a person may not be able to push out any poop. Or if they’re able to, it may come out in very small or thin pieces.
Anal stenosis: In rare cases, a person may have a narrowing of their anal canal, which is where poop passes through to exit the body. This is sometimes referred to as an anal stricture. It can cause poop to look thinner.
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How do doctors diagnose the cause of stringy poop?
There are different ways healthcare professionals can diagnose the cause of stringy poop. These include:
Stool sample: A healthcare professional may ask you to collect a stool sample. They can then use this to test for bacteria, viruses, and parasites. They can also check for markers of inflammation, which may be elevated in certain GI disorders like inflammatory bowel disease (IBD).
Fecal occult blood test: This test looks for blood in the stool that isn’t visible to the naked eye. It can be done in a healthcare office by collecting a small sample with a rectal exam. It can also be added to the tests for a stool sample.
Imaging: Some healthcare professionals may suggest imaging tests like an X-ray or a CT scan to get a better look at your internal organs. They may also suggest a barium enema, a special test that allows them to visualize the last part of the intestine near your anus.
Colonoscopy: This is the best way to get a good look at your intestine. This procedure uses a small camera that’s inserted into your anus while you’re sedated. Healthcare professionals can directly visualize the inside of your intestine, and if necessary, collect small tissue samples for testing.
When are fiber strings in your poop a sign of a problem?
It’s not uncommon to see a few fiber strings in your poop, or notice that your poop looks different than it normally does. But if you’re experiencing fiber strings or stringy stool in addition to the following symptoms, speak with a healthcare professional right away:
New or intense abdominal pain
Blood in your poop, which can look bright red or even black like tar
Loss of appetite
Nausea and vomiting
Weight loss
Even without these symptoms, it never hurts to check in with a medical professional for noticeable changes in your poop — especially if they last for several days or more.
Frequently asked questions
Healthy poop can look different from person to person. But in general, healthy poop is sausage-shaped with either smooth or bumpy edges. When you’re constipated, stool is usually hard or pebble-like with lots of lumps and bumps. When you have diarrhea, stool is usually unformed, very mushy, or completely liquid.
Long poops aren’t usually a cause for concern. In fact, this may be a sign of healthy digestion and full bowel movement. Your poop may be really long if you recently ate a large amount of food. Or it could be the release or resolution of recent constipation. If your poop is really long but soft, it could be a normal variation. But if it’s very long, and very firm, then it could be a sign of constipation.
After birth, a newborn baby’s poop will be dark green to black, tarry, stringy, and sticky. This is known as meconium, and it’s normal. After 3 to 4 days, it will start to become more yellow-green or lighter brown.
If you have tapeworms, pieces of them may detach in your poop. Tapeworms are often white, and may appear long or stringy. They can also appear short and look like grains of rice that move. So it’s easy to confuse tapeworms with stringy poop. If you’re ever unsure, a good place to start is taking photos to share with your primary care provider.
Parasitic infections like pinworms or tapeworms can cause white stuff in your poop. They may look like thin white threads in the toilet. But white or fuzzy stuff in your poop isn’t necessarily a medical problem. White specks of poop could be from undigested food like seeds or bean sprouts. Or it could be the remaining pieces of medications, like the outer part of certain pills. Other reasons your poop may change color include problems with your liver or pancreas. Sometimes problems with the organs can make stool appear pale or clay-like.
Healthy poop can look different from person to person. But in general, healthy poop is sausage-shaped with either smooth or bumpy edges. When you’re constipated, stool is usually hard or pebble-like with lots of lumps and bumps. When you have diarrhea, stool is usually unformed, very mushy, or completely liquid.
Long poops aren’t usually a cause for concern. In fact, this may be a sign of healthy digestion and full bowel movement. Your poop may be really long if you recently ate a large amount of food. Or it could be the release or resolution of recent constipation. If your poop is really long but soft, it could be a normal variation. But if it’s very long, and very firm, then it could be a sign of constipation.
After birth, a newborn baby’s poop will be dark green to black, tarry, stringy, and sticky. This is known as meconium, and it’s normal. After 3 to 4 days, it will start to become more yellow-green or lighter brown.
If you have tapeworms, pieces of them may detach in your poop. Tapeworms are often white, and may appear long or stringy. They can also appear short and look like grains of rice that move. So it’s easy to confuse tapeworms with stringy poop. If you’re ever unsure, a good place to start is taking photos to share with your primary care provider.
Parasitic infections like pinworms or tapeworms can cause white stuff in your poop. They may look like thin white threads in the toilet. But white or fuzzy stuff in your poop isn’t necessarily a medical problem. White specks of poop could be from undigested food like seeds or bean sprouts. Or it could be the remaining pieces of medications, like the outer part of certain pills. Other reasons your poop may change color include problems with your liver or pancreas. Sometimes problems with the organs can make stool appear pale or clay-like.
The bottom line
If you notice that your poop is stringier than usual, it’s not typically a cause for concern. It’s normal to have fluctuations in your digestion based on your routine and diet. But sometimes narrow, stringy poop can be a sign of an underlying medical condition. So if you have any concern or intuition that something else might be going on, don’t worry alone. Talk with a medical professional you trust.
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References
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