Steatorrhea, or fatty stool, describes frothy, foul-smelling stool that floats. Steatorrhea can happen after eating high-fat foods, but it may also indicate liver disease or another health condition.

Stool or feces contain a mixture of undigested nutrients. These include proteins, fibers, and salts. It also typically contains mucous, dead cells, or any other waste the body is able to excrete.

This article discusses what causes fatty stool, and its symptoms, diagnosis, and treatment.

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Steatorrhea is not usually a major health concern and typically happens after eating meals high in fat, fiber, or potassium oxalate.

Some foods that are especially high in indigestible or difficult to digest fats and fibers are likely causes of steatorrhea. They may include:

  • nuts, especially whole nuts with the skin or shell intact
  • spinach
  • oily fish
  • fatty foods
  • certain oils, such as mineral oil and castor oil
  • whole wheat products

However, people may find that foods that trigger fatty stools vary. If they are concerned, a person should consider keeping a food diary and speaking with a doctor about their diet.

Alcohol consumption may also cause steatorrhea, particularly if a person engages in chronic heavy drinking.

Severe or long term symptoms of steatorrhea may be a sign of a medical condition, such as a malabsorption disorder, enzyme deficiency, or gastrointestinal disease. Some medical conditions that may cause steatorrhea include:

In some cases, steatorrhea may result from taking certain medications. People should speak with a healthcare professional about potential risks and side effects before taking any medications. They should also report any side effects to their doctor.

Steatorrhea describes when a person passes loose but bulky stools with globs of fat and noticeable oil separation.

Short term symptoms

Mild or short term cases of steatorrhea may cause some limited discomfort. Additional symptoms of mild steatorrhea include:

  • foamy, frothy, or mucus-filled stool
  • foul-smelling stool
  • diarrhea or loose or runny stool that is bulkier than normal
  • pale stool, often a light brown, green, orange, or yellow
  • stool that floats
  • stool that appears to be covered in a thick, greasy film
  • stool that is difficult to flush away
  • abdominal pain, cramping, and bloating
  • gassiness

Long term symptoms and complications

Malnutrition and dehydration may be caused by severe or chronic cases of steatorrhea. Further, complications can develop as well, especially if a person has underlying medical conditions, such as celiac disease or chronic pancreatitis.

Symptoms and complications associated with severe or chronic steatorrhea include:

A person should speak with a healthcare professional if they experience steatorrhea that does not go away. A doctor can diagnose any underlying causes and recommend appropriate treatment for the condition and any complications.

A doctor will usually start the diagnostic process for steatorrhea by asking about a person’s symptoms, reviewing their medical history, and ordering laboratory tests.

The first laboratory test a healthcare professional may order is a fecal fat test, which assesses the fat content of stool.

Some doctors may use a 24 hour test. However, the standard method is the 72 hour fecal fat test.

To prepare for a 72 hour fecal fat test, an individual must consume 100 grams (g) of fat daily for 3 days prior to the test, and fast for a few hours directly before the test.

They will need to collect a stool sample using a collection kit and instructions and take the sample to their clinic or doctor’s office.

When consuming 100 g of fat daily, a healthy individual should excrete 7 g or less per day of fat in their stool. Healthcare professionals define steatorrhea as excreting more than 7 g of fat in a 24-hour period when consuming 100 g of fat daily.

If a doctor does diagnose someone with steatorrhea, they will likely request further tests, such as imaging tests and biopsies, to determine the underlying cause.

The treatment for steatorrhea depends on the cause and severity of symptoms.

In mild or short term cases, a person may find that limiting the consumption of foods that trigger symptoms, like those with high fat and fiber content, helps reduce the frequency of fatty stool. However, a person should speak with a doctor about how to maintain a healthy diet.

Severe or chronic cases of steatorrhea will typically need medical intervention. People with steatorrhea because of an underlying medical condition will require specific treatments, for example:

A person should speak with a doctor to find out which treatments are best for them.

Severe, chronic steatorrhea requires medical attention.

Fatty stool can also be a sign of several underlying medical conditions that require treatment. These include gastrointestinal diseases, enzyme deficiencies, or malabsorption disorder.

If a person experiences steatorrhea that does not go away, they should visit a doctor who can help identify the underlying cause and recommend appropriate treatment on an individual basis.

Steatorrhea refers to frothy, foul-smelling stool that floats. It may be loose but bulky and pale in color.

A person may experience steatorrhea after eating certain foods, such as those with high fat content. However, it may also result from a range of underlying health conditions, like chronic pancreatitis, SIBO, and malabsorption disorder.

People should speak with a healthcare professional if they experience steatorrhea that does not go away or keeps coming back. A doctor can work out the cause and recommend treatment.