Why is my poop green, black or pale?
General information, not health advice. Talk to your doctor or dietitian about your own symptoms.
Most color changes trace back to food or a medicine. A few colors should never be waited out.
Last updated ยท By Torstein Skulbru
Written by a software developer, not a clinician, from the sources listed below. How the guides are written.
The short version
Poop color usually comes down to food, a medicine, or how fast things moved through. Brown, green and yellow are common. Black, red and pale are different: read those three sections and do not wait them out.
Poop color chart
| Color | Most common causes | When to talk to a doctor |
|---|---|---|
| Brown | The usual color, in any shade from light to dark | A brown shade alone is no reason |
| Green | Food moved through fast, leafy greens, green food dye | Diarrhea for more than a few days, or a fever |
| Yellow | Food moved through quickly, rich or fatty meals, carrots, sweet potato, squash | Greasy, floating and unusually bad-smelling for more than a few days, or weight loss |
| Red | Beets, red food dye, tomato juice, cranberries, or blood | If you can't link it to food. Blood in poop should always be checked |
| Black | Iron tablets, bismuth (Pepto-Bismol), blueberries and other very dark foods, or bleeding | Black and sticky like tar with no link to iron, bismuth or food: get medical advice today |
| Pale, grey or clay | Too little bile reaching the gut, some anti-diarrhea medicines, very rarely dairy | Pale more than once or twice in a row. With yellow skin or eyes or dark pee, get medical advice today |
What color should poop be?
Brown is the usual color, and any shade from light to dark is common. Most of the time the exact shade comes down to what you ate. A brown shade alone is no reason to see a doctor.
Why is my poop green?
Green poop usually means food moved through fast, which is very common with loose poop. Spinach, kale and other leafy greens and green food dye can also turn it green. If it comes with diarrhea for more than a few days, or a fever, check in with a doctor.
Why is my poop yellow?
Yellow poop usually means food moved through quickly or the meal was rich or fatty, and it is common with loose poop. Carrots, sweet potato and squash can cause it too. If it's yellow, greasy, floats and smells unusually bad for more than a few days, or you're losing weight, book a check-up.
Why is my poop red?
Red poop can come from something red you ate or drank: beets, red food dye, tomato juice or cranberries. It can also be blood, so it is never worth guessing.
Worth a check-up
Most of the time it's something minor like piles (hemorrhoids), especially if it's bright red, but blood in poop should always be checked by a doctor.
If you can't link it to food, or you see blood in the bowl or on the paper, talk to a doctor. Blood in poop should always be checked.
A lot of blood, large clots, or bleeding that will not stop is an emergency. Call your local emergency number.
Why is my poop black?
Black poop most often comes from iron tablets or bismuth (Pepto-Bismol), and both are very common causes. Blueberries and other very dark foods can do it too.
Please get medical help today
Black, tar-like poop can be a sign of bleeding higher up in the gut.
If it's black and sticky like tar and you can't link it to iron, bismuth or food, get medical advice today. Don't wait.
Contact a doctor or urgent care now. If you feel faint, very unwell, or the pain is extreme, call your local emergency number.
Why is my poop pale, grey or clay-colored?
Pale poop usually means too little bile is reaching your gut. Some anti-diarrhea medicines can cause it, and very rarely dairy. Count it as worth mentioning to a doctor, not something to wait out.
Worth a check-up
Pale or clay-colored poop a few times in a row is worth mentioning to a doctor.
If it's pale more than once or twice in a row, book a check-up. If you also have yellow skin or eyes or dark pee, get medical advice today.
Pale poop together with yellow skin/eyes or dark pee should be checked quickly.
When should I talk to a doctor about poop color?
Red you can't link to food, black and tar-like, or pale more than once or twice in a row are the colors to talk to a doctor about. Cleveland Clinic also says to contact a provider if the color does not go back to brown within a few days. This is general information, not a diagnosis. If something seems off to you, trust that and talk to a doctor.
Color is only half of the picture. The Bristol stool chart covers shape and firmness.
Sources
- Cleveland Clinic: Poop color. Food and medicine causes by color; contact a provider if the color does not go back to brown within a few days.
- Cleveland Clinic: Clay-colored or pale stool. Pale poop usually means too little bile; call a provider if it stays clay-colored for more than a few days.
- NHS: Symptoms of bowel cancer. Blood in poo can look red or black; black or dark red poo needs urgent advice; a lot of blood or large clots is an emergency. Used here only for the blood and black-poo advice.
- NHS: Jaundice. Yellow skin or eyes with darker pee and paler poo than usual.
- NHS: Side effects of ferrous sulfate. Darker poo is common with iron tablets; black, tar-like or red poo, or blood, needs medical advice.
Keep a simple record to show your doctor: log it in three taps, on your phone.
