woman holding nose over metal smelling stool

Poop Smells Like Metal: Causes Of A Metallic Stool Odor

Poop is a natural part of life, and its smell can sometimes evoke curiosity or concern. One unusual smell that some people may encounter is a metallic smelling poop.

While this may seem strange, understanding the potential causes and contributing factors can help ease your mind and provide insight into your body’s processes.

A foul smelling poop could be attributed to a variety of factors, including your diet, medications, and certain medical conditions.

For instance, a high intake of iron-rich foods or iron supplements might cause a metallic odor due to the excess iron being excreted through fecal matter. In some cases, the smell can also be a result of gastrointestinal conditions, which may warrant further investigation by a medical professional.

Understanding Metallic Poop Smell

Causes of Metallic Smelling Poop

There are several reasons why one might wonder “why my poop smells like metal.” Some of these causes include the consumption of certain foods and supplements, as well as taking specific medications.

Ingesting foods rich in iron or certain preservatives can lead to a temporary metallic smelling stool. Similarly, some medications, such as certain types of antibiotics, can also contribute to this phenomenon.

Some possible causes of a metallic smelling stool include:

  • Iron-rich foods: Red meat, organ meats, leafy green vegetables, and fortified grains are all high in iron, which can contribute to a smell like metal in stool when consumed in large amounts.
  • Sulfur Rich Foods: Some sulfur-rich foods include kale, cabbage, onions, garlic, broccoli, nuts and seeds (especially almonds, Brazil nuts, peanuts, walnuts, and pumpkin and sesame seeds), eggs and dairy (whole eggs, cheddar, Parmesan and gorgonzola cheese, and cow’s milk), dried fruit, meat, organ meats, fish, other types of seafood, spices, legumes, and cruciferous vegetables such as arugula, Brussels sprouts, cauliflower, and radishes
  • Vitamin B supplements: Some over-the-counter supplements, specifically B vitamins, can cause a smelly poop when taken in high doses.
  • Medications: Antibiotics, antifungal drugs, and other medications may interact with gut bacteria or alter in the balance of digestive chemicals, resulting in a metallic poop smell in the bowel movement.

The Role of Diet and Supplements

Diet and supplements play a significant role in the overall smell of one’s stool. Consuming certain foods, such as those rich in iron or foods high in sulfur, can give feces a metallic or pungent odor.

Additionally, some supplements can contribute to this phenomenon, especially if they contain large amounts of certain minerals or vitamins.

Here are some diet and supplement factors that may contribute to poop smells metallic in your stool:

  • Iron-rich foods: As mentioned earlier, consuming large amounts of iron-rich foods can cause this smell. Some examples of iron-rich foods include red meat, organ meats, spinach, and fortified cereals.
  • Vitamin B supplements: Overconsumption of certain B vitamins, such as B6 and B12, may lead to a smell like metal in one’s stool.
  • Foods containing sulfur: Garlic, onions, eggs, and cruciferous vegetables like broccoli and cabbage are high in sulfur compounds which can alter the odor of stool.

To minimize the chances of experiencing a metallic foul smelling stool, it’s essential to maintain a balanced diet and avoid consuming excessive amounts of specific foods and supplements.

If the smell persists or is accompanied by other symptoms, it is advised to consult your healthcare professional for further evaluation.


older gentleman plugging nose from the smell

Common Gastrointestinal Disorders and Metallic Smelling Poop

Celiac Disease

Celiac disease is an autoimmune disorder that affects the small intestine, causing inflammation and damage to the villi. This results in malabsorption of nutrients, not having the ability to properly absorb nutrients can lead to various symptoms.

One possible explanation for a stool smells of metal in individuals with celiac disease is the presence of undigested food particles, as well as increased levels of certain metals, such as iron.

Some common symptoms of celiac disease include:

  • Stomach pain
  • Bloating
  • Diarrhea
  • Constipation
  • Fatigue

A strict gluten-free diet is the primary treatment for celiac disease, which can help alleviate symptoms and reduce inflammation in the intestines and digestive system.

Crohn’s Disease

Crohn’s disease is a type of inflammatory bowel disease (IBD) that affects the entire gastrointestinal tract.

It can cause inflammation and irritation in the intestines, leading to symptoms such as abdominal pain, diarrhea, and fatigue.

In some cases, metallic-smelling feces may be due to the presence of inflammation in the intestines, which can cause an imbalance in the gut bacteria, contributing to the odor.

Crohn’s disease symptoms can vary, but may include:

  • Abdominal pain
  • Diarrhea
  • Weight loss
  • Anemia
  • Fatigue

Treatment for Crohn’s disease often involves medications to reduce inflammation, as well as dietary and lifestyle modifications.

Ulcerative Colitis

Ulcerative colitis, another type of IBD, affects only the colon and rectum. It causes inflammation and ulcers in the inner lining of the large intestine, leading to symptoms such as abdominal pain, diarrhea, and bleeding.

A colonoscopy is often used to diagnose ulcerative colitis. Similar to Crohn’s disease, the presence of inflammation and changes in gut bacteria can contribute to a poop smell like metal in the stool.

Some common symptoms of ulcerative colitis include:

  • Pain in the abdomen
  • Diarrhea with blood or mucus
  • Bloody stool
  • Urgency to have bowel movements
  • Weight loss
  • Fatigue

Treatment for ulcerative colitis aims to manage symptoms and induce remission. This may involve medications, dietary changes, and in severe cases, surgery.

While each of these gastrointestinal disorders has specific causes and treatments, it is important to consult a healthcare professional for proper diagnosis and management.

A smelly stool may be an indication of an underlying health issue, and addressing the root cause can help alleviate this symptom.


several medication pills in an open hand

Medications and Side Effects


Antibiotics are a common cause of changes in the smell of stool. One antibiotic that has been known to cause a poop smell like metal in the stool is metronidazole. The stinky poop smell is due to the drug’s side effects, which can include gastrointestinal upset in the digestive system.

Some people also experience diarrhea and fart smell that have an unmistakable smell while taking metronidazole. It is important to remember that antibiotics should be taken as prescribed, and any concerns about side effects should be discussed with a healthcare provider.

Iron Supplements

Taking iron supplements can also lead to changes in the smell of the stool. Iron tablets are typically prescribed to treat iron-deficiency anemia or if gastrointestinal conditions, such as colorectal cancer, have caused a decrease in iron absorption.

Consuming iron supplements may cause side effects such as:

  • Dark colored stools
  • Constipation
  • Diarrhea
  • Headache
  • Unpleasant taste in mouth

These side effects can contribute to the farts smell metallic in the stool that smell bad. It is important to discuss any concerns with a healthcare provider, as well as follow the recommended dose and duration for the supplements.

If side effects become too bothersome, the healthcare provider may suggest alternative treatments or adjustments to the dosage.

Serious Health Conditions and Metal-Smelling Poop

Gastrointestinal Bleeding

Gastrointestinal bleeding can cause a change in poop odor, sometimes leading to blood in the stool and a smelly poop. This is because blood contains iron, which has a distinct metallic scent.

Bleeding can result from a variety of factors such as ulcers, gastritis, hemorrhoids, or even inflammatory bowel disease. If you suspect gastrointestinal bleeding, consult your doctor immediately for a proper diagnosis and treatment.

Chronic Liver or Kidney Disease

Chronic liver or kidney disease can also affect the smell of your poop. These conditions can cause an accumulation of waste products and toxins in your body that may result in a metal-like odor in your stool.

Liver disease affects the organ’s ability to filter out waste, while kidney disease impacts the elimination of waste through urine. If you are experiencing symptoms such as fatigue, jaundice, or stomach pain, it is essential to consult a medical professional for proper diagnosis and treatment.

Bowel Cancer Poop Smell

If poop smells like metal it could be indicative of bowel cancer. Bowel cancer affects the large intestine and can cause changes in the smell and consistency of stool.

In some cases, the metallic odor may be due to internal bleeding caused by the tumor. If you notice persistent changes in the odor or appearance of your stool, along with symptoms such as abdominal pain, rectal bleeding, change in bowel movements or unexplained weight loss, it is crucial to seek medical advice.

Early detection and treatment can improve the prognosis for bowel cancer patients.

When to Consult a Doctor About A Metallic Smelling Stool

If you notice that your poop smells like metal, it’s essential to pay attention to any accompanying symptoms and consider consulting a doctor.

Sometimes, changes in the smell of your feces can indicate underlying health issues. Here are a few instances in which you should consult a healthcare professional:

  • Persistent change in smell: If the metallic smell in your stool or gas persists for more than a few days and is not linked to any specific food or medication, it’s a good idea to consult a doctor. This could be a sign of an underlying issue that needs medical attention.
  • Blood in stool: A poop smell like metal in your stool could be due to the presence of blood, which can be a sign of gastrointestinal or digestive tract bleeding. This may be indicative of various pathologies, such as ulcers, inflammation, or even cancer. If you notice blood in your feces, it’s crucial to seek medical advice immediately.
  • Anemia or iron deficiency: A metallic smell in your stool may be related to anemia or an iron deficiency. Iron supplements can sometimes cause changes in the odor of your feces. If you are experiencing symptoms of anemia, such as fatigue, weakness, and shortness of breath, consult your doctor to discuss possible interventions.
  • Other gastrointestinal symptoms: If the stinky poop metallic smell in your feces is accompanied by other digestive system symptoms like abdominal pain, nausea, vomiting, or diarrhea, seek medical advice. These symptoms could be indicative of a range of gastrointestinal issues, including infections and inflammatory disorders.

Remember, it’s always better to err on the side of caution when it comes to your health and bowel habits.

If you have any concerns about the smell of your feces or experience any of the symptoms mentioned above, don’t hesitate to consult a doctor for a proper evaluation and appropriate treatment.

FAQ For Why My Poop Smells Like Metal

What causes poop to smell metallic?

A metallic smell in poop may be caused by actual metal, specifically iron. Iron is an important part of hemoglobin, a protein found in red blood cells that helps the cells carry oxygen throughout the body.

When bright red blood that is found in your stool, it may cause a metallic odor. This could be a sign of health conditions like inflammatory bowel disease (IBD) or colorectal cancer.

What are some other causes of metallic-smelling poop?

A diet high in meats, especially red meat, and a family history can point to colorectal or stomach cancer, as being a more likely cause of metallic-smelling stool.

Supplements or diet pills that you may be taking could also be a cause. Due to the preservatives and color dyes found in many of the vitamin pills that are commonly taken in modern society, an unusual metallic smell may be present.

Should I be concerned if my poop smells metallic?

If you notice a metallic smell in your poop, it is generally recommended to get checked out by a healthcare professional.

Clearly metallic-smelling bowel movements may be the sign of something entirely harmless like iron supplements or antibiotics. But it could also be a sign of a more serious underlying condition, so it’s best to get it checked out.

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