StoolSense

Poop Basics

Stool color guide

What does stool color mean and when should I worry?

Most stool color changes come from diet, food dyes, or supplements. The colors that deserve extra caution are black/tarry, bright red blood, and pale/clay - especially if they persist or come with dizziness, severe pain, fever, vomiting, weakness, or faintness. If you are unsure, seek medical care.

At a glance

Brown or tan (baseline)

Normal digestion; everyday variation is expected.

Green

Fast transit or greens; common, usually harmless.

Yellow or orange

Diet or bile changes; watch if persistent.

Red

Food dye or blood; context matters.

Black

Iron, meds, or possible bleeding.

Pale or clay-colored

Possible bile flow issue; not normal if repeated.

Key takeaways

  • Most one-off color changes are food/med related and settle within 24-48 hours.
  • Black/tarry stool, large amounts of bright red blood, or repeated pale/clay stool deserve prompt medical attention.
  • Iron and bismuth (Pepto) can make stool very dark; beets and red dyes can look scary but usually pass quickly.
  • Track color with Bristol type and obvious drivers (foods, iron/Pepto, antibiotics) so you can stop guessing.

Safety notes

  • Black, tarry, sticky stool (especially with weakness or dizziness)
  • Large amounts of bright red blood, clots, or bleeding that does not stop
  • Pale or clay-colored stool that repeats, especially with dark urine or yellow eyes/skin
  • Any color change plus severe pain, fever, vomiting, faintness, dehydration, or unexplained weight loss

What to track

  • Color + Bristol type
  • Time of day
  • Obvious drivers (beets/dyes, iron/Pepto, antibiotics, new supplements)
  • Symptoms if present (pain, fever, dizziness, vomiting, weakness)

If you are deciding between “food dye” and “urgent,” start here: Red or black stool: food dye or urgent care?

Quick answer

Most stool color changes are from food, dyes, or supplements and may pass within 24–48 hours. Colors that need extra caution are black/tarry, bright red blood, or pale/clay stools, especially if they repeat or come with dizziness, severe pain, fever, vomiting, weakness, or faintness. This week, log color + Bristol type and one likely driver.

When to seek care

Seek medical care if you see black/tarry stool, large amounts of bright red blood, clots, or repeated pale/clay stool, especially with dark urine or yellow eyes/skin. Also seek care for any color change plus severe pain, fever, vomiting, faintness, dehydration, or unexplained weight loss.

What to track this week

  • Color + Bristol type
  • Time of day
  • Obvious drivers (beets/dyes, iron/Pepto, antibiotics, new supplements)
  • Symptoms if present (pain, fever, dizziness, vomiting, weakness)

A simple 7-day test

  1. Log color + Bristol type daily for 7 days.
  2. Note one likely driver (food/dye, iron/Pepto, antibiotics) to avoid guesswork.
  3. If the color repeats without an obvious driver, move to a clinical check.

Evidence note

Color alone does not diagnose a condition. It is a useful signal when combined with persistence and symptoms.

Brown or tan (baseline)

Most people sit somewhere in the brown-to-tan range. Day-to-day shifts are normal and can reflect what you ate, hydration, and how fast things moved through you.

Green stool

Green is commonly:

  • Faster transit (bile has less time to turn brown)
  • Leafy greens or food dyes

If green comes with severe diarrhea, fever, dehydration, or it keeps happening without an obvious explanation, get checked.

Yellow or orange stool

Yellow/orange can show up after supplements, certain foods, or changes in bile flow. A one-off change is common. Persistent pale, chalky, or clay-colored stool (not just “lighter brown”) is different - treat that as a red flag.

Red stool

Red can be as simple as beets, tomato skins, or red dye. It can also be blood.

If you see bright red blood, large amounts, clots, or you also feel dizzy, weak, or have worsening pain, seek care.

Black stool

Iron supplements and bismuth (Pepto-Bismol) can turn stool very dark.

If you are not taking iron or bismuth and you see black, tarry, sticky stool, treat it as possible bleeding and seek urgent care.

Pale or clay-colored stool

Repeated pale/clay stool can signal a bile flow issue (liver, gallbladder, or pancreas). If it repeats beyond a day or two - especially with dark urine, yellow eyes/skin, fever, or upper-right belly pain - get medical advice promptly.

What to tell a clinician (copy/paste)

If you decide to seek care, this is the fastest handoff:

  • When it started + whether it is getting better or worse
  • The exact color (brown, green, bright red blood, black/tarry, pale/clay)
  • Any meds/supplements (especially iron, bismuth, antibiotics, laxatives)
  • Recent foods that can change color (beets, dyes, activated charcoal)
  • Symptoms: pain, fever, vomiting, dizziness, weakness, faintness, weight loss

Use photos only if you are comfortable. You do not need perfect documentation to get help.

FAQs

How long should a food-related color change last? +
Often 24-48 hours after the food or dye is out of your system. If the color persists longer without an obvious cause, or you feel unwell, consider medical advice.
What can make stool green? +
Green stool is often faster transit (bile has less time to turn brown) or foods/dyes (spinach, kale, blue dye). If it lasts more than a few days or comes with fever, severe diarrhea, or dehydration, consider medical advice.
Can iron or Pepto make stool black? +
Yes. Iron supplements and bismuth (Pepto-Bismol) can darken stool to deep green/black. If you are not taking these and you see black, tarry, sticky stool, treat it as possible bleeding and seek urgent care.
When should I worry about red stool? +
Red can be from beets, tomato skins, red dye, or hemorrhoids - but it can also be bleeding. If you see bright red blood, clots, large amounts, or you feel dizzy or weak, seek medical care.
What does pale or clay-colored stool mean? +
Repeated pale or clay stool can signal a bile flow problem (liver, gallbladder, or pancreas). If it repeats for more than a day or two - especially with dark urine, yellow eyes/skin, fever, or upper-right belly pain - get medical advice promptly.
What should I track so I can stop guessing? +
For 7 days, log color + Bristol type + timing, and note obvious drivers: iron/Pepto, antibiotics, new supplements, beets/dyes, alcohol, and travel. Add symptoms (pain, fever, dizziness, vomiting) because they change urgency.

References

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