Fat in Stool: What Causes It and How to Prevent It

The presence of fat in stool may indicate the existence of a gastrointestinal disease. Unfortunately, the symptoms of steatorrhea are often subtle, so it's important to see a doctor for early detection.
Fat in Stool: What Causes It and How to Prevent It

Last update: 27 May, 2022

Stool is comprised of waste that appears as a result of the digestion of food consumed throughout the day. It usually has a characteristic appearance and composition according to our diet. Sometimes, however, it’s possible to observe fat in stool, which is a sign that something isn’t working properly.

The presence of micelles, or fat deposits in stool, is a clinical manifestation called steatorrhea. Studies show that pancreatic lipases, bile acids, and the intestinal epithelium mediate fat digestion and absorption. Therefore, the malfunction of any of these parts can lead to the onset of this condition.

Unfortunately, the epidemiology of steatorrhea is difficult to determine, as it’s often not evident at the onset. In these cases, certain laboratory tests are necessary to confirm the presence of fat in stool.

Symptoms of steatorrhea

The characteristics of the stool often change due to the presence of fat in the stool. In this regard, they may become bulkier, foul-smelling, and pale. These stools often float in the toilet, making them more difficult to flush.

In some cases, steatorrhea is often more evident, so it’s possible to observe fat micelles in the toilet, similar to what happens when mixing water and oil. One of the main causes of this clinical manifestation is malabsorption syndrome, so people may have other general symptoms:

Children may have more severe symptoms, including stunted growth and delayed puberty. It’s important to remember that young children need a certain amount of nutrients for their development.

A child with abdominal pain.
Fatty stools in children should be treated to prevent growth and development problems.

You may also be interested in the following article: Chronic and Acute Diarrhea: Causes and Treatment

Causes and risk factors

Fat in the stool usually appears when there’s a deficiency in the production of pancreatic lipases or bile acids. It can also result from damage to the epithelium of the first portion of the small intestine. Therefore, many illnesses affecting the liver, pancreas, or intestine can produce the appearance of steatorrhea.

All conditions capable of causing exocrine pancreatic insufficiency (EPI) may be at the origin of the symptom, due to the lack of enzyme production. Some studies state that chronic pancreatitis is the most frequent cause of EPI in adults.

A common condition that can cause the appearance of fat in the stool is celiac disease. This is a disease that affects the epithelium of the small intestine, which hinders the absorption of fats.

Other diseases in which steatorrhea may appear are the following:

  • Cystic fibrosis
  • Cholestasis
  • Crohn’s disease
  • HIV enteropathy
  • Whipple’s disease
  • Parasitosis, such as giardiasis
  • Pancreatic or intestinal surgeries

How to diagnose fat in stool?

Doctors can diagnose the presence of fat in the stool based on clinical findings. However, different laboratory tests are necessary to confirm the diagnosis. The specialist may first ask about the general characteristics of the stool. In addition, they’ll look for signs that indicate the presence of underlying diseases.

The necessary laboratory tests consist of a qualitative and quantitative analysis of fat in stool samples. The qualitative will seek to demonstrate the presence of macroscopic fat in the sample. It consists of adding a special dye that will change color in the presence of fat.

On the other hand, the quantitative analysis will seek to determine the amount of fat expelled in a period of time. For this, the patient will need to collect different stool samples over the course of 1, 2, or 3 days. The result will be positive when there’s the expulsion of more than 7 grams of fat in the stool in 24 hours.

The preparation for the quantitative analysis of fat in the stool is very precise. Individuals must maintain a diet in which they consume 100 grams daily in the 3 days before the test. It may be an uncomfortable and cumbersome diet, but it’s the most accurate way to determine steatorrhea.

Available treatments for fat in stool

Treatment for the presence of fat in stool will depend on the disease that’s causing this manifestation. In general terms, it’s best to maintain a balanced diet low in lipids, as well as proper hydration. Foods that trigger symptoms should also be identified to avoid them.

General measures, such as rest and quitting smoking, can also help reduce symptoms. A decrease in alcohol intake is also usually beneficial, as well as the administration of antiflatulents, antacids, and antidiarrheals.

The administration of exogenous pancreatic enzymes is useful in the case of exocrine pancreatic insufficiency. For their part, the implementation of a celiac diet and education are essential for patients with a diagnosis of celiac disease. Lastly, the administration of ursodeoxycholic acid and surgery are the first-line treatment for cholangitis, for example.

Gluten free grains.
If the patient has celiac disease, they should follow a corresponding gluten-free diet to reduce steatorrhea.

When to consult a physician

Everyone should consult a specialist if they notice the presence of micelles or fat droplets in the stool. It’s also important to seek professional help in the presence of an increase in the number of daily stools or pale or very foul-smelling stools.

The presence of fat in stool may indicate the presence of a malabsorption syndrome. In this sense, sudden and involuntary weight loss and abdominal discomfort should be warning signs.

Fat in stool: A problem not to be underestimated

The presence of fat in stool can be a difficult manifestation to notice because its symptoms are usually very nonspecific at the beginning. It’s characterized by sudden and subtle changes in the stool, especially in its odor, color, and quantity. In addition, it can produce the appearance of general signs as the underlying disease progresses.

This clinical manifestation may be the result of multiple pathologies affecting the pancreas, biliary tract, or intestinal epithelium. These can generate a deficient absorption of nutrients, which complicates the general condition. In this sense, you must seek medical assistance in the presence of any abnormal symptom.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.