How To Read Your Poop (And Why You Should)

Written by Emma Loewe: Writer, author, and editor of Cultured. Her writing explores the intersection of nature, climate, and human health. Emma is the author of “Return to Nature” and “The Spirit Almanac.”
Reviewed by Jennie O’Grady: Senior SciComms Specialist at Seed Health

By the time poop makes a touchdown in your toilet, it’s had to maneuver 20-30 feet of the intestinal tract, face liters of highly acidic juice in the stomach, and traverse up to 100 trillion bacterial cells in the gut.^1,2,3 Its shape, color, size, consistency, and odor can tell you a lot about the status of all these biological touchpoints and then some.

Stool is a vital diagnostic tool that gets delivered right to us multiple times a week. But it’s up to us to interpret it before we flush.

Ready to decode your defecation? Here’s how to scan your poop’s shape, color, size, and more for clues about your digestive health. 

Consistency and Shape

Your stool is around 75% water and 25% solid waste (primarily undigested plant fibers but also fats, proteins, mucus, bile, and microbial matter).⁴ So, its appearance on any given day can tell you quite a bit about whether you’re drinking enough water or consuming enough nutrient-dense foods.

Consulting the Bristol Stool chart can give you a quick read on the composition and consistency of your stool.⁵ Developed in 1997 and now used in clinical and research settings around the world, the chart classifies human poop into seven categories:  

• TYPE 1: Separate hard lumps
• TYPE 2: Lumpy and sausage-like
• TYPE 3: Sausage shape with cracks
• TYPE 4: Smooth, soft sausage shape
• TYPE 5: Soft blobs with clear edges
• TYPE 6: Mushy consistency
• TYPE 7: Liquid consistency

Your stool type can change by the week and in some cases, by the day. Here’s how to interpret all seven:

Types 1 and 2: Lacking in liquid

If your stools appear lumpy, dry, and sausage-like, or small and hard like pebbles, it could be a sign that your GI system is clogged. During digestion, the intestines remove excess water and nutrients from your stool before it makes its way out. If your stool is sitting in the colon for a long time, it may lose too much water and become dry and difficult to pass. 

Here are a few ways you can loosen up those harder BMs:

• Drink more water
• Up your fiber intake
• Exercise and walk after meals

Types 3, 4, and 5: The superstars of stool

Sausage or snake-like in shape, stool types 3, 4, and 5 are not watery or dry, and they’re expelled easily without strain. If you spot one of these in the bowl, keep doing what you’re doing!

Types 6 and 7: Need time to tighten up

If your stools have a mushy or liquid texture, it’s a sign that your colon is not extracting enough water from your food. (This likely means you’re not absorbing proper nutrients from your food, either).^4,6 Loose stools can happen when digested food material doesn’t spend enough time in the GI tract. 

They can also occur if something you eat draws water into the colon. Gluten and lactose are common culprits, particularly in people with food intolerances.⁴ 

Here are a few ways to slow things down and bulk things up if you’ve just passed a 6 or 7:

• Drink more water
• Up your fiber intake
• If loose stools are recurring, get tested for food intolerances 

Buoyancy

Got a floater? If your stool is buoyant once it hits the bowl, it’s not a cause for concern. In fact, it’s likely a good sign!

Stools float when they have a higher concentration of gases (mostly methane), which are byproducts of bacterial fermentation.¹⁰

The bacteria in your colon play the vital role of breaking down stubborn food particles that have withstood the earlier phases of digestion. Simple sugars and most starches are digested in the upper GI tract more easily than high-fiber foods (vegetables, fruits, legumes, nuts and seeds, and whole grains), which tend to require microbial intervention.

Once these fibers reach your colon, your bacterial entourage breaks them down for energy, producing byproducts like gut-strengthening SCFAs in the process. Gas is also a common metabolite of this feeding frenzy (hence why upping your vegetable intake might make you need to toot more).¹¹ If some of this gas gets taken in by your stool, it will float instead of sink. 

Since fiber is an essential component of a strong, diverse gut microbiome and floating stools can be a signal of adequate fiber intake, they’re usually something to celebrate.

EXPLORE FURTHER: What Is the “Best” Diet for Your Gut?

However, in select cases, floaters can signal a fat malabsorption issue. If yours are also consistently pale, foul-smelling, or oily, it’s worth flagging them to a doctor.¹² 

Color

Stool is (usually! hopefully!) brown due to bile—a digestive fluid that’s produced in the liver. In the process of breaking down food and eliminating waste, bile transports bilirubin (made from old red blood cells) into the intestines, where it is converted into byproducts (urobilinogen and stercobilin) that give poop its brown hue.¹³ 

Medical conditions that affect bile production can cause poop to change color. However, so can certain foods. If your stool takes on one of these hues, here are some potential edible culprits:

• Red or pink: Seeing any shade of red in the toilet bowl is alarming, but consider what you’ve eaten recently before freaking out. Beets, for example, can impart stool with a pink-red hue since they contain natural pigments that are not fully metabolized and absorbed in the digestive system.¹⁴ Some artificially dyed foods—looking at you, Flamin’ Hot Cheetos—can also lead to bright red stools.¹⁵ 
• Dark or black: Dark-color foods like licorice or blueberries can lead to stool that appears black. Certain supplements, like iron, may also darken stool.¹⁶
• Green: Spinach, kale, and other leafy greens can cause poop to take on an emerald hue.¹⁷
• Spotted: Small clumps of colorful food may also decorate your BMs. This is more common with plants that are high in cellulose—a component of plant cell walls that has strong molecular bonds that are difficult for the body to break down.¹⁸ So, no need to fret if you spot corn, peas, or carrots in your bowl—you may just want to eat slower and chew your food a bit more.

If your stool color changes are temporary and you can trace them back to something you ate, there’s no need to worry. However, if color shifts are drastic, longer lasting, and/or accompanied by other changes, flag them to a doctor.

Odor

Your sh*t doesn’t stink—it just smells like microbial decay. As your gut bacteria break down different food particles, they emit volatile organic compounds such as indole. Indole and its derivatives, like skatole, are largely what gives your poop its signature scent.¹⁹ 

In small amounts, scents like skatole are actually very pleasant (fun fact: they’re responsible for the aroma of flowers such as jasmine and orange blossoms). However, things start to get a little, shall we say, pungent, when they’re present in higher concentrations.²⁰

Certain foods, such as red meat and cruciferous vegetables, tend to lead to more VOCs during the digestion process, so your poop may smell more strongly after you eat them.^21,22

Occasional changes in bathroom odor are no big deal. But if your stool smells are especially foul or are accompanied by changes in frequency, color, etc., flag it to a doctor. It could be a first whiff of food allergies, infections, or underlying conditions.

Frequency

For some people, going a day without pooping is no big deal. For others, it’s a bona-fide bathroom emergency.

It turns out that poop frequency varies with diet, body composition, and even hormones—so there’s a wide range of what’s considered “normal.” As long as you’re having a BM between three times a week and three times a day, you’re in the Goldilocks zone.^23,24

If you’re going no. 2 less than three times a week, here are some questions to ask yourself:

• Am I ignoring the urge to poop? When you hold it in, your stool stays in the colon for longer than it needs to. This could lead to excess water absorption, making stools less frequent and harder to pass.
• Am I eating enough fiber? Remember: Fibrous foods give stool bulk and help it move through the intestines. Load your plate with plenty of fruits, vegetables, nuts, and whole grains. 
• Am I drinking enough water? Staying hydrated can help keep your stool moist and easier to pass.
• What medications am I on?: Infrequent poops can be a side effect of medications such as anticholinergics (used to treat COPD and incontinence) and narcotic agents.⁴
• Am I moving around enough? Exercise—even gentle movement like walking after meals—can help stimulate digestion.²⁵ Here’s an overview of the best workouts for your gut health.
• Am I particularly stressed? Acute (short-term) and chronic (long-term) stress can throw off the enteric nervous system, also known as the second brain.²⁶ 

EXPLORE FURTHER: 5 Things to Try Next Time You’re Backed Up

And if you’re stuck on the throne upwards of three times a day, here’s what to consider: 

• Am I eating triggering foods? Diets high in fat, protein, or spice may lead to looser, more frequent stools in some cases.^27,28 
• Am I drinking too much coffee? Coffee (even decaf) is known to stimulate bowel movements by activating the muscles in the stomach and colon.^29,30
• Is it time to check in with a doctor? If your poop schedule is interfering with your life, you should reach out to a healthcare professional. In some cases, frequent BMs are a sign of inflammation or infection somewhere in the GI tract, so medication may be necessary.⁴ Your doctor can also test you for underlying allergies or intolerances. 

Ease of Expulsion

Ideally, once you feel the urge to poop, it’s easy for you to do so quickly and without strain. As a society, we’ve normalized reading on the toilet, but in reality, you should only have time to get through a page or so.

If the process is taking a while or becoming painful, trying out a new toilet position could help.

Poop position is more important than we give it credit for. The reason why comes down to your anorectal angle—the angle between your rectum (where poop is stored before evacuation) and anus (where it eventually leaves the body). A muscle called the puborectalis, which pulls on the rectum to prevent any premature exits, also plays a role in evacuation ease and speed.

When you sit straight up, the puborectalis stays tight and your anorectal angle sits at a sharp 100 degrees. When you squat, however, the puborectalis muscle relaxes and the anorectal angle begins to open to ~126 degrees, allowing stool to pass more freely.^31,32

Keeping a Defecation Posture Modification Device (DPMD)—in other words, a stool for your stool—next to your toilet can help you open up to smoother, easier exits. No reading material required. 

The Key Insight

Your poop’s shape, size, consistency, color, and even odor can provide valuable clues about the state of your digestive system. The key is to get to know what’s normal for your stool, so you can recognize when something looks, smells, or feels off. 

Brushing up on the journey food takes before it reaches your toilet bowl can help make you an even more discerning defecation decoder. Here’s our complete guide to digestion—from eating to excreting.