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Published on: 2/10/2026

Poop Black? 5 Causes for Women 65+ and When to See a Doctor

Black stool in women 65+ is often from harmless causes like iron supplements, dark foods, or bismuth-containing medicines, but it can also signal upper digestive bleeding or, rarely, stomach or intestinal cancer. Seek care promptly if it is tarry or sticky, lasts more than 2 to 3 days, occurs without iron or bismuth use, or you have weakness, dizziness, shortness of breath, stomach pain, vomiting blood, or fainting. There are several factors to consider and important details that can change next steps, so see the complete guidance below.

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Explanation

Poop Black? 5 Causes for Women 65+ and When to See a Doctor

Noticing that your poop is black can be surprising—and understandably concerning—especially as we get older. For women age 65 and up, black or very dark stool is fairly common and often not an emergency, but it can sometimes signal a medical issue that needs attention.

This guide explains five common causes of black poop in women 65+, how to tell when it may be serious, and when to speak to a doctor. The goal is to keep you informed without causing unnecessary worry.


What Does "Black Poop" Mean?

Black stool can range from dark brown to jet black. It may look sticky, shiny, or tar-like and may have a strong odor.

Doctors often use the term "melena" when black stool is caused by digested blood, usually from the upper digestive tract (such as the stomach or small intestine). However, not all black poop contains blood.

Understanding the cause is key.


1. Iron Supplements (Very Common)

Iron supplements are one of the most frequent causes of black poop, especially in women over 65.

Why this happens:

  • Iron is not fully absorbed by the body
  • Excess iron is excreted through stool
  • This can darken stool to a deep green or black color

Important notes:

  • This is normal and harmless
  • Stool is usually firm and not sticky
  • No stomach pain or weakness is present

If you started iron recently and your poop turned black soon after, this is likely the reason.

👉 Do not stop iron supplements without talking to your doctor, especially if you are being treated for anemia.


2. Certain Foods or Drinks

Some foods naturally darken stool and can make it look black.

Common culprits include:

  • Black licorice
  • Blueberries
  • Dark chocolate
  • Beets (can also cause red stool)
  • Very dark leafy greens

What to expect:

  • Color change lasts 1–3 days
  • Stool texture remains normal
  • No pain or fatigue

If your poop is black after eating dark foods, and returns to normal shortly after, it's usually not a concern.


3. Medications Like Pepto-Bismol or Aspirin

Some medications can turn stool black, particularly those containing bismuth subsalicylate (found in Pepto-Bismol).

Other medications that may contribute:

  • Aspirin (especially daily use)
  • Anti-inflammatory drugs (NSAIDs)
  • Blood thinners (indirectly, if bleeding occurs)

Bismuth reacts with sulfur in your digestive system, forming a black substance that darkens stool.

✅ This type of black poop is temporary and harmless, as long as:

  • You feel well otherwise
  • There is no dizziness or weakness

If you're unsure whether a medication is responsible, you can use a free AI-powered Black or tarry stool symptom checker to quickly assess your symptoms and get personalized guidance on what to do next.


4. Stomach or Intestinal Bleeding (More Serious)

One of the more serious causes of black poop is bleeding in the upper digestive tract.

Possible sources include:

  • Stomach ulcers
  • Inflammation of the stomach lining (gastritis)
  • Tears in the esophagus
  • Complications from long-term NSAID use

When blood is exposed to stomach acid, it turns black, leading to tarry-looking stool.

Warning signs may include:

  • Sticky, shiny black poop
  • Strong, unpleasant odor
  • Fatigue or weakness
  • Lightheadedness
  • Shortness of breath

This is not something to ignore, particularly for women over 65, who may have a higher risk of ulcers or medication-related bleeding.


5. Colon or Stomach Cancer (Rare, but Important)

While uncommon, black poop can sometimes be linked to cancer in the stomach or upper intestines.

Important perspective:

  • Most black stool is not cancer
  • Cancer-related bleeding is usually slow and painless
  • Symptoms may develop gradually

Possible accompanying signs:

  • Unexplained weight loss
  • Ongoing fatigue
  • Loss of appetite
  • Persistent changes in bowel habits

Because early detection makes a major difference, it's essential to speak to a doctor if black stool continues without a clear explanation.


When Should Women 65+ See a Doctor?

While many causes of black poop are harmless, some require medical care.

Speak to a doctor promptly if:

  • Black poop lasts more than 2–3 days
  • You are not taking iron or bismuth medications
  • Stool looks tarry or sticky
  • You feel weak, dizzy, or short of breath
  • You have stomach pain or chest discomfort

Seek urgent medical help if:

  • You feel faint or collapse
  • You have rapid heartbeat
  • You notice vomiting blood
  • Black stool appears along with severe abdominal pain

These could indicate internal bleeding, which can be life-threatening if left untreated.


Why Age Matters

As we age:

  • The stomach lining becomes more sensitive
  • Medication use increases
  • Chronic conditions are more common

This makes women 65+ more vulnerable to digestive bleeding, even from medications they've taken for years without problems.

Regular checkups and open conversations with your healthcare provider are essential.


What a Doctor May Do

If you report black poop, your doctor may:

  • Review medications and supplements
  • Order blood tests to check for anemia
  • Test stool for hidden blood
  • Recommend imaging or endoscopy if needed

These steps help determine whether the cause is harmless or serious.


A Helpful First Step You Can Take

If you're concerned about your symptoms and want immediate answers, try Ubie's free Black or tarry stool symptom checker—an AI-powered tool that helps you understand possible causes, assess urgency, and prepare for your doctor visit with personalized insights in just minutes.


The Bottom Line

For women 65 and older, poop black is often caused by:

  • Iron supplements
  • Certain foods
  • Medications like Pepto-Bismol

However, it can also be a sign of digestive bleeding or other serious conditions.

Trust your instincts. If something doesn't feel right—or if black stool appears without an obvious reason—speak to a doctor. Early evaluation can be reassuring and, in some cases, life-saving.

Your health matters, and asking questions is always the right choice.

(References)

  • * Batalis IN, et al. Clinical approach to upper gastrointestinal bleeding in the elderly. Front Med (Lausanne). 2023 Jul 11;10:1229792. doi: 10.3389/fmed.2023.1229792. PMID: 37497127; PMCID: PMC10373801.

  • * Laine L. NSAID-induced gastrointestinal bleeding: a comprehensive review of mechanisms, prevention, and management. J Intern Med. 2016 Feb;279(2):167-78. doi: 10.1111/joim.12411. Epub 2015 Sep 2. PMID: 26235128.

  • * Lau JY, et al. Peptic ulcer disease in the elderly: A review of risk factors, diagnosis, and management. World J Gastroenterol. 2011 Dec 28;17(48):5213-22. doi: 10.3748/wjg.v17.i48.5213. PMID: 22219616; PMCID: PMC3253303.

  • * Sami SS, et al. Angiodysplasia of the gastrointestinal tract: a clinical review. World J Gastroenterol. 2014 Jun 28;20(24):7555-67. doi: 10.3748/wjg.v20.i24.7555. PMID: 24966601; PMCID: PMC4073099.

  • * Gralnek IM, et al. Upper gastrointestinal bleeding in older patients: Causes, diagnosis, and management. Drugs Aging. 2011 Nov 1;28(11):901-13. doi: 10.2165/11593330-000000000-00000. PMID: 21978204.

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