Fishy-smelling stool can be alarming. While often linked to diet, it can sometimes indicate underlying health issues. This article explores the potential causes of fishy-smelling bowel movements and when to seek medical advice.
What Causes Fishy-Smelling Poop?
Several factors can contribute to stool that smells like fish. These include:
Diet
The most common culprit is diet. Foods rich in choline, such as fish (especially saltwater fish), eggs, and liver, can produce a fishy odor in stool. This is because choline breaks down into trimethylamine (TMA) in the gut. While the body usually converts TMA into a odorless compound, some individuals may excrete excess TMA, leading to a fishy smell.
Trimethylaminuria (TMAU)
TMAU, also known as fish odor syndrome, is a rare metabolic disorder where the body can’t properly break down TMA. This results in a buildup of TMA, which is released in sweat, urine, and feces, causing a strong fishy odor. TMAU can be inherited or acquired later in life.
Infections
Certain infections in the digestive tract, like bacterial vaginosis or giardiasis, can alter the gut flora and lead to malabsorption of fats. This can result in foul-smelling stools, sometimes described as fishy.
Liver or Kidney Problems
The liver and kidneys play crucial roles in filtering waste products. If these organs are not functioning correctly, it can lead to the accumulation of certain compounds in the body, potentially causing a fishy odor in stool.
Malabsorption
Conditions like celiac disease or Crohn’s disease can interfere with nutrient absorption in the intestines. Undigested fats can then be broken down by bacteria in the gut, producing foul-smelling stools, including a potential fishy odor.
Medications
Some medications, particularly antibiotics, can disrupt the balance of bacteria in the gut. This disruption can lead to changes in digestion and the production of foul-smelling stool.
When to See a Doctor
While a fishy smell in your poop is often due to diet, it’s important to consult a doctor if:
- The smell is persistent and doesn’t improve with dietary changes.
- You experience other symptoms like abdominal pain, diarrhea, fever, or weight loss.
- You suspect you might have TMAU.
Diagnosing the Cause
A doctor can help determine the underlying cause of fishy-smelling stool by:
- Reviewing your medical history and dietary habits.
- Performing a physical examination.
- Ordering stool tests to check for infections or malabsorption.
- Conducting blood tests to assess liver and kidney function.
- Referring you to a specialist for further evaluation if necessary. For instance, a genetic test can confirm a diagnosis of TMAU.
A doctor examining a patient.
Conclusion
Fishy-smelling poop can be caused by various factors, ranging from dietary choices to underlying medical conditions. While often benign, persistent fishy odor warrants medical attention to rule out any serious health issues. Consulting a doctor can help diagnose the cause and determine the appropriate course of action.
