Stool usually sinks, because it is more dense than water. It can sometimes float and not be a cause for concern. However, in some cases, floating stool may indicate the presence of a medical condition, and a person should contact a doctor.

If an individual’s stool floats often, it may be the result of their diet or a medical condition.

This article will provide information about some of the causes of floating stool. It will also discuss when a person’s stool indicates the need to seek guidance from a doctor.

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Stool’s ability to float is usually related to air. A high fiber diet and gas can cause stool to float.

However, if a person’s stool never sinks, it may be an indication of an underlying health condition, such as:

Excess fat in stool can also lead to floating stool. This can happen if a person consumes a large quantity of fat in their diet or if they have a condition that affects fat absorption, such as Crohn’s disease.

A diet high in fiber leads to increased bacterial fermentation during digestion. This produces more air, which can get trapped in stool, causing it to float.

Many high fiber foods, such as beans, Brussels sprouts, broccoli, and cauliflower, can cause gas. A 2020 study found that switching from a low fiber diet to a diet rich in fiber increased bloating, especially when the new diet was also rich in protein.

Some people also develop gas when they change their diet. If stool floats after an individual has eaten a new food or has switched to a new diet, gas could be the culprit.

Research from 2016 notes that 95% of adults and children in the United States do not consume enough fiber. Recommendations for fiber intake vary by age and sex.

Females aged 19–50 years should consume at least 25 grams (g) of fiber per day, while males in the same age group need at least 38 g of fiber daily.

GI infections can cause floating stool.

Some infections may cause gas, which can become trapped in the stool, lowering its density. In other cases, certain infections impair the body’s ability to absorb food, causing malabsorption. This can lead to fatty stools that float.

One example includes giardiasis. This is a parasitic infection that results in greasy stools that float.

Q:

What other GI infections can cause floating stool?

Anonymous

A:

Any GI infection can cause your stool to float, because the gas that the virus, bacterium, or parasite creates causes the stool to float. Other GI infection examples include those caused by Escherichia coli and Salmonella.

Cynthia Taylor Chavoustie, MPAS, PA-CAnswers represent the opinions of our medical experts. All content is strictly informational, and people should not consider it to be medical advice.

Some GI disorders can cause stool to float.

The authors of a 2015 study found that 26% of people with functional bowel disorders, such as irritable bowel syndrome and functional dyspepsia, had floating stools.

Additionally, 3% of those with functional GI disorders, which are a group of disorders that affect movement in the digestive tract, had floating stools.

For some individuals, floating stool may be the first warning sign of a GI or bowel problem. When floating stool occurs alongside other symptoms, such as pain, diarrhea, bloating, or constipation, it may signal an underlying GI issue.

According to research from 2021, floating stools are a symptom of a malabsorption syndrome. The stool may also be greasy and large and smell foul.

Examples of malabsorption syndromes that can lead to floating stool are fat malabsorption and carbohydrate malabsorption.

Fat malabsorption is one of the most common syndromes and can lead to steatorrhea. This is an increase of fat in stool, causing it to float. Although floating stool may be a sign of steatorrhea, a 2017 article observes that stool sticking to the toilet bowl is a more specific sign.

Steatorrhea can also occur due to a variety of malabsorption conditions, including small intestine disorders and liver and biliary disease.

Disorders that affect the small intestine can cause steatorrhea. People who have had a portion of their small intestine surgically removed, such as to treat Crohn’s disease, may also experience steatorrhea.

The liver produces bile, which helps the body digest food. When little or no bile reaches the intestines, it may result in a fatty stool. A person may also lose weight or develop diarrhea. Liver disease, blocked bile ducts, and gallstones may cause a fatty stool.

Carbohydrate malabsorption also causes stool to float. It occurs when a person’s body is unable to absorb starch, lactose, and sucrose. Carbohydrates that the body does not absorb ferment in the colon, leading to acidic stool, bloating, and flatulence. This gas can become trapped in the stool, causing it to float.

One important cause of carbohydrate malabsorption is lactose intolerance, which is the inability to metabolize lactose properly. This occurs when an individual’s digestive system produces too little of an enzyme known as lactase. It is also the most common cause of malabsorption.

People with lactose intolerance may experience bloating and diarrhea when they consume milk, cheese, or other dairy products.

As a 2017 article explains, some conditions affecting the pancreas can lead to a fatty stool due to fat malabsorption. Malabsorption can occur when the pancreatic enzymes or bile does not travel in sufficient quantities to the small intestine.

The result is a fatty stool that may float or be difficult to flush. The stool may also be white or very pale. Additionally, a person may notice that they have very dark urine.

Floating stool can also occur as a result of pancreatic cancer or pancreatitis.

Pancreatic cancer causes stool that is greasy and light in color. A person may also experience itchy skin, poor appetite, and weight loss, among other symptoms.

Pancreatitis is inflammation of the pancreas. It can lead to pain in the upper abdomen that may also spread to the back. Additionally, a person may experience:

It is not possible to diagnose conditions affecting the pancreas based on a person’s symptoms alone. Pancreatic disorders are serious, so it is essential to get help and treatment as soon as possible.

Floating stools are not usually a cause for concern, as they can result from gas being trapped in the stool and from a high fiber diet. However, if the symptom persists, a person may wish to contact a doctor.

It is advisable to seek guidance from a healthcare professional if:

  • a floating stool also looks very fatty or greasy, and the symptom persists
  • a person experiences chronic constipation or diarrhea
  • the stool is very light or pale
  • a person begins losing weight unintentionally
  • a person with an underlying medical condition develops changes in their bowel habits
  • a person has very dark urine

If an individual suspects that they have pancreatitis, they should seek medical attention as soon as possible, especially if the following symptoms occur:

  • pain that begins in the upper abdomen that:
    • begins slowly or suddenly
    • spreads to the back
    • is mild or severe
    • lasts for several days
  • fever
  • vomiting
  • nausea
  • a swollen abdomen
  • a fast heartbeat

Stool is the body’s way of eliminating waste, and it typically reflects a person’s diet. Floating stool, changes in stool color, and other temporary changes in bowel habits are usually not a sign of a serious medical condition.

However, a person should contact a doctor if symptoms persist or get worse. A doctor can do a variety of tests to reach a diagnosis.

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