What the Color of Your Poop Can Tell You About Your Gut Health

Don't forget to look before you flush: The hue of your stool can tell you a lot about your health and even alert you to warning signs that you may need to get checked out.

Here, gastroenterologists break down what to know about the color of your poop.

First, though, let's back up and talk about why your poop is usually, well, that brown-ish color.

"Stool color is typically tan, or anywhere from light brown to dark brown," says Monica Borkar, MD, a gastroenterologist with NorthShore University HelathSystem in Glenview, Illinois.

Your liver excretes a substance called bile into your gastrointestinal (GI) tract, which itself is anywhere from dark yellow to light orange. "As it interacts with the contents of your digestive system (what you eat), it changes color," Dr. Borkar explains. And out comes brown.

But what if you look back and see a strange color in the toilet? Should you laugh? Put it on IG? (Don't put it on IG.) Panic? Call your doctor?

"In general, changes in the color of your stool are influenced by what you eat and usually nothing to worry about," says Dr. Borkar. However, there are some that warrant that call.

Here's what seven stool colors might mean and when you should worry:

Green poop is likely caused by your diet. Spinach, green Jell-O, blue-green colored ice creams (or anything that contains dye), black licorice and black jelly beans are all culprits, Dr. Borkar says.

Your poop color should return to normal once the food has passed through your system.

If you have diarrhea, your stool may appear yellow-colored or greenish, says Jacqueline Wolf, MD, a gastroenterologist at Beth Israel Deaconess Medical Center in Boston. Diarrhea means things are speeding through your system too quicky for stool to properly form. That also means there's less time for your stool to convert into a darker color.

Check out five common causes of diarrhea (and when to call your doctor), along with the best and worst foods for diarrhea.

Yellow poop might also be a result of excess fat in your diet and could be a digestive side effect of a low-carb diet like keto.

Again, it's going to be something you ate. Blueberries are the main culprit of a dark blue stool that can almost look black, says Dr. Wolf.

This is where things get tricky. The culprit can be totally benign, like beets, red Jell-O or red sports drinks, says Dr. Wolf. (Side note: If you are preparing for a colonoscopy, skip the red-dyed stuff, as it can be confused with blood.) Blood from hemorrhoids or a cut on the anus — if, say, you were constipated — are also potential culprits.

However, red poop can also have more concerning causes, like bleeding from lower down in your colon. Blood in your stool is also a red flag symptom for colorectal cancer; additional symptoms include a change in bowel habits (like diarrhea or constipation) that lasts for more than a few days, cramping or abdominal pain and unintended weight loss, according to the American Cancer Society (ACS).

If you think you're too young for that cancer, think again: Rates of colorectal cancer and deaths from the disease are slowly rising in people under age 50, accounting to 2020 statistics published in the ACS journal ‌CA: A Cancer Journal for Clinicians‌. Because young people don't routinely get colonoscopies to check for this cancer, it's even more important to act when you see blood in your stool (meaning: call your doctor).

A darker red color may also stem from bleeding in the GI tract, particularly where the colon joins the small bowel, says Dr. Wolf. Colon cancer, diverticulosis, colitis and inflammation in the colon can contribute to this maroon shade. Call your doctor if you see this hue in the bowl.

This is another color you generally don't want to see. Black poop can sometimes be benign: Taking Pepto-Bismol can turn the stool a very dark color, as can iron supplementation or eating a lot of blueberries, says Dr. Wolf. These are things you should tell your doctor about so he or she can properly evaluate you.

"Black stool can also mean bleeding from the esophagus, the stomach or the small intestine," Dr. Borkar says. That can be caused by a stomach ulcer or (rarely) a tumor in the upper GI tract. "The stool becomes black because the blood goes through the GI tract and is broken down by digestive enzymes," she explains.

Kaopectate (an anti-diarrhea medication) can turn stools lighter. That said, clay-colored stools can also be indicative of an obstruction in the liver or bile ducts, says Dr. Borkar.

Gallstones or a tumor in your pancreas can all block these ducts. Call your doctor right away for unusually light-colored stools, especially if you have pain that would indicate something like a blocked bile duct.

Poop that's red, black or clay/white definitely warrants a call to your physician. And if you're concerned about any other funky stool shade, it's not a bad idea to hop on the phone. Dr. Wolf recommends asking yourself these three questions before you do, so you can give your doc the full picture:

1. Did you add something new to your diet? Did you eat spinach or beets? Did you eat anything heavy in food dyes?
2. Have you taken any new medications, whether prescription, over-the-counter or a supplement?
3. Do you have any other physical symptoms? A major change in bowel habits, unintentional weight loss (losing weight when you poop), localized pain, nausea, vomiting and fatigue are all symptoms to let your doctor know about.

You might be an expert in your own body, but it can be tough to properly evaluate poop color changes on your own. So if you have any questions, don't hesitate to ask. Trust us, your doctor has heard it all.