The Curious Case of Blue Poop (and How to Get It Back to Brown)

When you do your standard post-poop inspection, the results are (hopefully) consistent: a couple of smooth brown logs resting at the bottom of the toilet bowl. But every now and then, you find a surprise…like a blue turd.

You do a double-take. It’s not a dream. It looks like someone dipped your dump in blue dye. What gives?

Normally, your stool color ranges from tan to brown to dark green. That’s from the breakdown of bile in your liver. But certain factors—especially your diet—can turn your turds a shade of blue.

Keep reading to find out what causes blue poop, whether you should worry about it, and when you can expect your bowel movements to go back to brown.

“Why Is My Poop Blue?”

The most common cause of blue poop is your diet. Foods that are naturally blue or have artificial blue food coloring can easily change the color of your poo. Here are some of the usual culprits:

Blueberries
Grapes
Plums
Currants
Raisins
Beets
Blue liquor, especially Blue Curacao
Grape soda
Foods with blue food dye, like blue icing
Imitation blueberries (like the ones added to muffin mixes)

When you consume blue foods, the compounds may not get fully absorbed by your digestive system. When the unabsorbed blue stuff mixes with bile and digestive fluids, it can leave your poop with a blue tint when it snakes out of your butthole.

Another potential cause of blue stool is a medication called Prussian blue (Radiogardase), which is used to remove radioactive compounds from someone’s body. We’ll take a wild guess you haven’t been exposed to radiation lately, so you can check that off the list of potential causes.

Lastly, there’s a rare condition called porphyria that’s been known to turn stool blue or bluish-purple. Porphyria affects your ability to break down heme, a compound in your body that contains iron. On top of blue poop, other symptoms of porphyria include nausea, breathing problems, anxiety, and seizures. Unless you’re dealing with those, chances are you don’t have a rare disease.

What About Blue-Green Poop?

Sometimes poop takes on a bluish-green color. In fact, this tends to be more common than straight up blue stool. Here are a few reasons that might happen:

Bile passing too quickly through your intestinal tract
Diarrhea
Baby formula
Eating green foods, such as frostings, gelatin, and green-colored drinks
Taking iron supplements
Eating leafy green vegetables like spinach or kale

Is It Bad If Your Poop Is Blue?

Don’t freak out if your poop is blue. It’s usually a harmless result of blue pigments or dyes working their way through your digestive system. If you ate something blue, you might notice the effect for a day or two until the pigment works its way out of your system.

It’s totally normal for food to alter the color of your poop, especially when the food is made with artificial dyes. If you’re curious, check out our thorough analyses of orange poop and yellow diarrhea.

What to Do If Your Poop Is Blue

If you notice your poop is blue, the first thing to do is think back to what you ate over the past day or two. Did you scarf down a bunch of blueberries? Eat a cake with blue icing? Drink a bunch of Blue Curacao at the bar?

Assuming you identify the culprit, there’s not much to do but wait for the blue to run its course. If you’re feeling eager, drink more water, eat plenty of fiber, and get some exercise to make yourself poop and clear your system faster.

If your poop doesn’t go back to its normal brown color after a couple of days, it won’t hurt to talk to a healthcare provider.

When to Talk to a Doctor About Blue Poop

The occasional blue poo is nothing to worry about. However, there are a few scenarios in which you might want to talk to a doc:

Your Poop Stays Blue for Several Days: Poop that stays blue longer than usual could indicate something wrong in your gut.
You Have Painful Bowel Movements: Pooping should be pleasurable, not painful. Don’t be afraid to tell your doc about painful poops, regardless of the color.
You Find Blood In Your Stool: Red streaks in your poop can be a sign of bleeding in your gastrointestinal tract.
Your Stools Are Narrow: Pencil-thin stools can indicate gut health issues like a bowel obstruction—these warrant medical help ASAP.

Brown or Blue, We’ll Wipe For You

Just like fingerprints, no two poops are ever the same. Some are colossal, some are tiny. Some are smooth, some are lumpy. Most are brown, but your diet can turn your turds all sorts of funky colors—including blue.

After wiping billions of butts since 2012, we’ve seen our fair share of crazy dookies in the toilet, but we’re always proud to clean ‘em up. Whether your poop is brown or blue, DUDE Wipes prevent any leftovers from lingering in your third pit. Say goodbye to swamp ass and dingleberries and hello to the cleanest crack you’ve ever had.