What causes stools to float. How can diet affect stool buoyancy. When should floating stools be a cause for concern. What tests might a doctor perform for persistent floating stools. How are floating stools typically treated.

The Science Behind Floating Stools

Floating stools are a common occurrence that can often be attributed to dietary factors or temporary digestive issues. The buoyancy of stool is primarily determined by its gas content and density. When stools contain excessive gas or have a lower density than water, they tend to float rather than sink.

To understand this phenomenon better, it’s essential to grasp the basics of the digestive process:

1. Food enters the stomach and is partially broken down.
2. The partially digested food moves into the small intestine, where most nutrient absorption occurs.
3. Unabsorbed material passes into the colon (large intestine).
4. The colon absorbs water from the remaining food residue.
5. The final product is eliminated as feces.

During this process, various factors can influence the composition and buoyancy of the stool, leading to floating stools.

Common Causes of Floating Stools

While floating stools are often harmless, they can be caused by various factors. Understanding these causes can help individuals determine whether their floating stools are a cause for concern or simply a result of dietary choices.

Dietary Factors

One of the most common reasons for floating stools is diet. Certain foods can increase gas production in the digestive system, leading to more buoyant stools. Some examples include:

• High-fiber foods (e.g., fruits, vegetables, whole grains)
• Lactose-rich foods (for those with lactose intolerance)
• Artificial sweeteners
• Carbonated beverages

Is a change in diet always the culprit behind floating stools? Not necessarily. While dietary changes are a common cause, other factors can contribute to this phenomenon.

Malabsorption

Malabsorption occurs when the body struggles to absorb nutrients properly. This can lead to floating stools, particularly if fat absorption is impaired. Conditions that may cause malabsorption include:

• Celiac disease
• Chronic pancreatitis
• Cystic fibrosis
• Short bowel syndrome

How can malabsorption be identified as the cause of floating stools? Floating stools due to malabsorption are often accompanied by other symptoms such as weight loss, abdominal pain, and frequent, foul-smelling bowel movements.

When Should Floating Stools Be a Concern?

In most cases, floating stools are not a cause for alarm and will resolve on their own without treatment. However, there are certain situations where floating stools may indicate an underlying health issue that requires medical attention.

Should you be worried if your stools float occasionally? Generally, no. Occasional floating stools are usually harmless and often related to temporary diet changes or mild digestive issues.

However, you should consider consulting a healthcare professional if you experience:

• Persistent floating stools (lasting several weeks)
• Floating stools accompanied by unexplained weight loss
• Stools that are pale, clay-colored, or have an unusually foul odor
• Floating stools with blood or mucus
• Chronic diarrhea or changes in bowel habits
• Abdominal pain or discomfort

These symptoms could indicate more serious digestive issues or malabsorption problems that require medical evaluation.

Diagnostic Approaches for Persistent Floating Stools

If you’re experiencing persistent floating stools or other concerning symptoms, your healthcare provider may recommend various diagnostic tests to identify the underlying cause.

Medical History and Physical Examination

Your doctor will likely start by taking a detailed medical history and performing a physical examination. They may ask questions such as:

• When did you first notice the floating stools?
• How frequently do they occur?
• Have you made any recent changes to your diet?
• Are you experiencing any other symptoms?
• Do you have a family history of digestive disorders?

Stool Analysis

A stool sample may be requested to check for signs of infection, inflammation, or malabsorption. This test can help identify issues such as:

• Bacterial or parasitic infections
• Inflammatory bowel disease
• Fat malabsorption

Blood Tests

Blood tests can provide valuable information about your overall health and may help identify conditions that could be causing floating stools. These tests might include:

• Complete blood count (CBC) to check for anemia or infection
• Liver function tests
• Pancreatic enzyme levels
• Celiac disease antibody tests

Imaging Studies

In some cases, your doctor may recommend imaging studies to examine your digestive tract. These may include:

• Abdominal ultrasound
• CT scan
• MRI

How long does it typically take to receive a diagnosis for persistent floating stools? The timeline can vary depending on the complexity of your case and the tests required. In some instances, a diagnosis may be made quickly based on your symptoms and initial test results. In other cases, it may take several weeks to complete all necessary tests and receive a definitive diagnosis.

Treatment Options for Floating Stools

The treatment for floating stools depends on the underlying cause. In many cases, simple dietary modifications may be sufficient to address the issue.

Dietary Changes

If your floating stools are caused by dietary factors, your healthcare provider may recommend:

• Reducing intake of gas-producing foods
• Avoiding artificial sweeteners
• Limiting consumption of carbonated beverages
• Gradually increasing fiber intake to improve overall digestive health

Treating Underlying Conditions

If floating stools are due to an underlying medical condition, treatment will focus on addressing that specific issue. For example:

• Celiac disease: Adopting a gluten-free diet
• Lactose intolerance: Using lactase enzymes or avoiding dairy products
• Chronic pancreatitis: Pancreatic enzyme replacement therapy
• Infections: Appropriate antibiotic or antiparasitic medications

Can floating stools be completely eliminated with treatment? In many cases, yes. However, the success of treatment depends on accurately identifying and addressing the underlying cause.

Preventing Floating Stools

While not all causes of floating stools can be prevented, there are several steps you can take to promote healthy digestion and reduce the likelihood of experiencing floating stools:

• Maintain a balanced diet rich in fruits, vegetables, and whole grains
• Stay hydrated by drinking plenty of water
• Eat slowly and chew food thoroughly to aid digestion
• Manage stress through relaxation techniques or exercise
• Avoid excessive alcohol consumption
• Exercise regularly to promote healthy bowel function

Is it possible to prevent all instances of floating stools? While these measures can help reduce the frequency of floating stools, occasional occurrences are normal and not necessarily a cause for concern.

The Role of Gut Health in Stool Buoyancy

The health of your gut microbiome plays a crucial role in digestion and can influence stool characteristics, including buoyancy. A diverse and balanced gut microbiome contributes to efficient digestion and nutrient absorption, potentially reducing the likelihood of floating stools.

How can you promote a healthy gut microbiome? Consider the following strategies:

• Consume a variety of fiber-rich foods to feed beneficial gut bacteria
• Include fermented foods in your diet (e.g., yogurt, kefir, sauerkraut)
• Consider taking a high-quality probiotic supplement
• Limit the use of antibiotics unless medically necessary
• Reduce stress, as it can negatively impact gut health

By maintaining a healthy gut microbiome, you may improve your overall digestive health and potentially reduce the occurrence of floating stools.

Floating Stools in Children: What Parents Should Know

Floating stools can occur in children as well as adults. While the causes are often similar, there are some specific considerations for parents to keep in mind.

Are floating stools in children always a cause for concern? Not necessarily. As with adults, occasional floating stools in children are usually harmless. However, parents should be aware of potential red flags that may warrant medical attention:

• Persistent floating stools accompanied by poor growth or weight loss
• Chronic diarrhea or changes in bowel habits
• Abdominal pain or discomfort
• Signs of dehydration
• Pale or clay-colored stools

If you notice any of these symptoms in your child, it’s advisable to consult with a pediatrician for proper evaluation and guidance.

Common Causes of Floating Stools in Children

Some common causes of floating stools in children include:

• Dietary factors (e.g., high-fiber foods, excessive fruit juice consumption)
• Lactose intolerance
• Celiac disease
• Gastrointestinal infections
• Cystic fibrosis (in rare cases)

How can parents help prevent floating stools in children? Encouraging a balanced diet, limiting sugary drinks and excessive fruit juice intake, and promoting good hygiene practices can help maintain healthy digestion in children.

Myths and Misconceptions About Floating Stools

There are several myths and misconceptions surrounding floating stools that can lead to unnecessary concern or confusion. Let’s address some of these common misunderstandings:

Myth 1: Floating stools always indicate a serious health problem

Fact: While floating stools can sometimes be a sign of underlying health issues, they are often harmless and related to dietary factors or temporary digestive changes.

Myth 2: Floating stools mean you’re not getting enough nutrients

Fact: Floating stools alone do not necessarily indicate poor nutrient absorption. Many healthy individuals may experience floating stools due to their diet or other benign factors.

Myth 3: You should aim for stools that always sink

Fact: There is no “ideal” stool buoyancy. Both floating and sinking stools can be normal, depending on various factors such as diet and individual digestive patterns.

Myth 4: Floating stools are always caused by excess fat in the stool

Fact: While excess fat can cause stools to float, it’s not the only reason. Increased gas content is a more common cause of floating stools.

Is it important to dispel these myths about floating stools? Absolutely. Understanding the facts about floating stools can help individuals make informed decisions about their digestive health and avoid unnecessary anxiety or medical interventions.

The Connection Between Floating Stools and Overall Health

While floating stools are often benign, they can sometimes provide valuable insights into your overall health and digestive function. Understanding this connection can help you become more attuned to your body’s signals and make informed decisions about your health.

Digestive Efficiency

The buoyancy of your stools can offer clues about how efficiently your digestive system is processing food. For example:

• Occasional floating stools may indicate a healthy, fiber-rich diet
• Persistent floating stools could suggest issues with nutrient absorption or digestive enzyme production
• Changes in stool buoyancy might reflect alterations in your gut microbiome

Hydration Status

The water content of your stools can affect their buoyancy. Well-formed stools that sink may indicate good hydration, while very dry, floating stools could suggest inadequate fluid intake.

Metabolic Health

In some cases, floating stools may be associated with metabolic conditions such as:

• Diabetes (which can affect nutrient absorption)
• Hyperthyroidism (which can increase gut motility)
• Pancreatic insufficiency (leading to fat malabsorption)

How can monitoring your stool characteristics contribute to better overall health? By paying attention to changes in your stool, including buoyancy, you may be able to detect early signs of digestive issues or other health concerns. This awareness can prompt timely medical consultations and potentially lead to earlier interventions when necessary.

Remember, while stool characteristics can provide valuable health information, they should be considered alongside other symptoms and health indicators. Always consult with a healthcare professional for proper evaluation and diagnosis of any persistent or concerning changes in your bowel habits.

Stools – floating Information | Mount Sinai

Floating stools

Stools that float are most often due to poor absorption of nutrients (malabsorption) or too much gas (flatulence).

Food passes from the stomach into the small intestine. In the small intestine all nutrient absorption occurs. Whatever has not been absorbed by the small intestine passes into the colon. In the colon most of the water is absorbed from the food residue. The residue is then eliminated from the body as feces.

Considerations

Most causes of floating stools are harmless. In most cases, floating stools will go away without treatment.

Floating stools alone are not a sign of an illness or other health problem.

Causes

Many things can cause floating stools. Most of the time, floating stools are due to what you eat. A change in your diet may cause an increase in gas. Increased gas in the stool allows it to float.

Floating stools may also happen if you have a gastrointestinal infection.

Floating, greasy stools that are foul smelling may be due to severe malabsorption, particularly if you are losing weight. Malabsorption means your body is not properly absorbing nutrients.

Most floating stools are not caused by an increase in the fat content of the stool. However, in some conditions, such as long-term (chronic) pancreatitis, the fat content is increased.

Home Care

If a change in diet has caused floating stools or other health problems, try to find which food is to blame. Avoiding this food may be helpful.

When to Contact a Medical Professional

Tell your health care provider if you have changes in your stools or bowel movements. Contact your provider right away if you have bloody stools with weight loss, dizziness, and fever.

What to Expect at Your Office Visit

Your provider will perform a physical exam and ask questions about your medical history and symptoms, such as:

• When did you first notice the floating stools?
• Does it happen all the time or from time to time?
• What is your usual diet?
• Does a change in your diet change your stools?
• Do you have other symptoms?
• Are the stools foul smelling?
• Are the stools an abnormal color (such as pale or clay-colored stools)?

A stool sample may be needed. Blood tests may be done. In most cases, however, these tests will not be needed.

Treatment depends on the specific diagnosis.

Höegenauer C, Hammer HF. Maldigestion and malabsorption. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 104.

Schiller LR, Sellin JH. Diarrhea. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 16.

Semrad CE. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 131.

Last reviewed on: 5/4/2022

Reviewed by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

Why Do Stools Float Sometimes?

Written by WebMD Editorial Contributors

• What Are Floating Stools?
• Why Would Stools Float?
• When To See a Doctor
• Treatment
• Prevention

Stools, or poop, usually sink to the bottom of the toilet, but sometimes, they can float. If your poop never sinks to the bottom of the toilet bowl, you may have too much gas in your intestines.‌

Normally, floating stools aren’t a cause for concern. Read on to learn more about why stools float, what floating stools say about your health, and more.

When stools float, it means the poop stays on the surface of the toilet water instead of sinking. Normally, poop sinks to the bottom of the toilet bowl.‌

Floating poop doesn’t mean you’re sick, but it can be a symptom of various conditions.

There are several reasons why poop floats and never seems to sink.

Too much gas. You may have too much gas in you due to your diet, which can make your stools float. 

Some people think that floating poop is caused by fat, but it’s usually caused by gas. Research has indicated that once floating stools were degassed, they weighed the same as sinking poop. This indicates that gas was responsible for making floating stools float, rather than fat inside the poop.

Gas in your digestive system is usually caused when you swallow air or eat certain types of foods that break down into gas. 

If you eat a high-fiber diet with a lot of vegetables and fruits, you may get floating stools because digesting high-fiber foods releases more air during digestion. This leads to air or gas being trapped in the stool, making it float in the toilet bowl.

Medical conditions. If your poop floats, there’s a slight chance you have steatorrhea, which means you have too much fat in your poop. Steatorrhea indicates you can’t absorb fat properly, and it can be a symptom of the following conditions:

• Celiac disease
• Exocrine pancreatic insufficiency (EPI) due to cystic fibrosis and chronic pancreatitis
• Diseases affecting small intestines such as tropical sprue, Whipple disease, and lymphoma
• Bile acid deficiency

You may also have the following conditions if you have floating poop:

• Gastrointestinal infection
• Malabsorption, which means you’re not absorbing nutrients as well as you should

Floating stools don’t necessarily mean you have an underlying health condition. To determine if a health condition is causing this, you should be on the lookout for other indicators. 

If your floating stools are smelly, sticky, or bloody, for example, you should see a doctor. Your doctor will give you a proper diagnosis and walk you through the process of understanding your condition if you have one. Here’s a closer look at what might cause these symptoms. ‌

Smelly and sticky stools. Smelly and sticky stools are typically a symptom of nutrient malabsorption. This means your body isn’t able to completely absorb and digest nutrients from your gastrointestinal tract due to damage to the small intestine, not having enough pancreatic enzymes, liver disease, HIV/AIDs, or other conditions.

If your floating stools are smelly and appear sticky, you should contact your doctor.

Blood in your stool. If your floating poop is accompanied by blood, it could be caused by:

• Bleeding in your anus or rectum
• Cancer of your digestive system
• Blood vessel abnormalities
• Inflammatory Bowel Disease such as Crohn’s Disease or Ulcerative Colitis
• Ulcers in the stomach or small intestine
• Polyps
• Diverticulitis ‌

If you find blood in your stools, you should see a doctor. If you’re experiencing weight loss, dizziness, or fever in addition to finding blood in your stools, you should talk to your doctor immediately. You should also get emergency medical help if there is a lot of blood in your poop, or if it is maroon or black and tarry.‌

Your doctor will be able to determine what is the exact cause of bloody poop through imaging tests and physical exams.

When you visit your doctor, they will likely ask you several questions about your medical history and your current health to determine why you have floating stools. They will also ask you about your diet and how long you’ve been having this issue so they can make any needed diet and medication recommendations.

Unless there is a medical condition causing you to have floating poops, there is no need to do anything to treat or prevent them.

Monitor your pooping habits. Always be aware of any changes to your stool and bowel movements. If you’re suddenly pooping more or less, or your poop looks very different, you should report these changes to your doctor. Your doctor will find it easier to diagnose any health conditions you may have if you keep an organized record about your pooping habits.

Changing your diet. Sometimes, preventing floating poop can be as easy as changing your diet, since floating poop can be caused by eating foods that cause you to have more gas.

You should avoid the following foods if you have a problem with too much gas:

• Hard candy
• Fizzy or carbonated drinks
• Gum‌

Keep a food diary so you can keep track of what you eat and narrow down what foods are giving you gas. You should bring this diary to your doctor so you can talk to them about how you can change your diet.

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How can our faeces help in early diagnosis?

We all poop, and even princesses don’t do it with violets. We’ll tell you what to pay attention to!

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Health

Health problems

What do these symptoms mean?

For some, the process of defecation is uncomfortable and unpleasant, associated with pain or shame. For others, it’s just part of the “cycle of life.” Babies inevitably go through the exciting process of getting to know the contents of their diapers.

In our culture, going to the bathroom “big” is almost never discussed publicly. But there is no need to be ashamed of this process – we all sit on a faience throne from time to time. Shameful inattention can even be harmful – our feces can “tell” about what is happening in the body and how it can be helped.

What is feces made of?

Mainly from undigested food, proteins, bacteria, minerals and other substances passing through the intestines. Every person is unique when it comes to feces, but there are a few common signs in shape, size, and odor that may indicate an unhealthy or unhealthy gastrointestinal tract.

What should be a normal stool?

Healthy feces can be as varied and unique as the people who produced them. But there are several general criteria by which you can evaluate the results of your digestive creativity:

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Color

The natural color for faeces is brown. Bilirubin is responsible for it – a pigment compound formed during the breakdown of red blood cells in the body.

Shape

We’re not cube-pooping wombats, so our bowels assume the more traditional, familiar shapes of feces—a log or a sausage. However, as we will learn later, various other options are possible that indicate problems.

Size

Feces should not come out in small “goat” balls (we will also talk about this later). The “standard” length is 5-6 centimeters, which is due to the ease of passage of feces through the intestines.

Consistency

Here the normal range is quite wide – normal feces can be both harder and softer. Deviations in one direction or another may indicate problems with digestion or an imbalance of fiber in the diet.

Duration of the process

If a person sits in the toilet for a long time, we believe that he is most likely pooping (or perhaps trying to hide from mumbling children for at least ten minutes). But for a healthy body, the process of defecation takes no longer than a couple of minutes. Therefore, if you spend more time in the toilet, this is an occasion to think about it.

What is the shape of feces and what does it indicate?

1. Goat balls

Hard small lumps that come out with difficulty usually indicate constipation. The frequent appearance of such a consistency is a reason to reconsider your diet.

2. Fat Caterpillar

Feces may be sausage-shaped but hard and lumpy in texture. This is also a sign of constipation.

3. “Sausage”

Faeces not too hard, not too soft, with small cracks on the surface. Gold standard, well done! Continue in the same spirit.

4. “Snake”

Feces are soft, smooth and long, shaped like a snake. In general, this is a variant of the norm.

5. Jellyfish

Feces are small in size, like goat balls, but have a soft texture and a fairly distinct shape. Usually such feces indicate a lack of fiber in the diet, so it is worth sticking to vegetables and cereals.

6. “Vegetable puree”

Feces are “airy” and soft, with jagged edges. This type of stool is closer to diarrhea, so drink plenty of fluids.

7. “Blotography”

Feces are completely liquid, there are few or no solid particles at all. This is diarrhea, or, as the people say, diarrhea. Feces passed through the intestines too quickly and did not have time to form.

What can stool color indicate?

How important is color when it comes to poop? It turns out yes. It helps to understand what is happening inside the body.

The normal color of feces, as we have already said, are shades of brown. A small greenery is also not terrible and may not be a sign of a problem. The following colors of feces should attract your attention:

Black

Who among us has not observed black feces with mild horror after taking a blister of activated charcoal? Surely there are such people, but there are hardly too many of them in the Russian expanses. Other “safe” causes of black feces can be iron supplements, bismuth preparations, hematogen, and even licorice.

But if you haven’t used anything like this, immediately go to the doctor – the black color of the feces can be caused by digested blood, which means that somewhere in the upper gastrointestinal tract there is bleeding.

Green

Small greens, as we have already mentioned, are not terrible.

But if the stool is more green than brown, then you may have one of two reasons: either you eat too many greens, or the stool passes through the intestines too quickly. In the latter case, bilirubin simply does not have time to color the stool in the usual brown color.

Pale, whitish or clay-colored

A color that is too light may indicate a lack of bile. We need it for healthy digestion and is normally produced by the liver and gallbladder. If the stool is too light, you may have a clogged bile duct, so don’t put off going to the doctor.

Pale stools can also be a side effect of certain medications.

Red

Yes, it’s blood. Perhaps problems with hemorrhoids, possibly bleeding in the lower gastrointestinal tract (as we already know, the higher the source of bleeding, the more time the blood has to digest).

Well, or you ate beets. Or cranberries. Or tomatoes.

Yellow

Greasy, foul-smelling yellow feces may indicate too much fat that has not been digested. It may also be associated with malabsorption of nutrients (for example, celiac disease).

Is it true that feces do not sink, as in the well-known proverb?

Normally, feces should just sink. They begin to swim when the density decreases, which happens due to an increase in the amount of water or gases in the composition.

Another cause may be malabsorption, the malabsorption of nutrients in the small intestine. In this case, the “big swim” may be accompanied by mild constipation.

When can we talk about constipation?

It turns out that constipation is not only a situation of long “sessions in parliament”. From a medical point of view, you can talk about constipation if you have a bowel movement less than three times a week!

There can be many reasons: from a nervous breakdown to problems with the nerves in the pelvic area, from diabetes to pregnancy. We humans are gentle creatures, and a huge number of factors affect our digestion. Many animals “from nerves” also stop pooping first. Take the same cats – after moving or strong excitement, the poor animal may not go to the pot for 3-4 days.

But back to homo sapiens. If you suffer from constipation, try drinking more water and eating vegetables, fruits, and legumes. And don’t forget to move – at least walk. There is a good chance that the problem will be solved.

A not very physiological posture can make defecation difficult. Why this happens can be clearly seen in the extremely ironic commercial with the prince and the unicorn.

When should I see a doctor?

If stool problems persist for more than a couple of days, you should consult a doctor. Green stool or a strange shape happens to everyone from time to time, but recurrence is a sign of a problem.

Chronic constipation can cause bowel obstruction, and chronic diarrhea can make it difficult to absorb essential nutrients and lead to severe dehydration. These conditions can also be signs of more serious illnesses.

Signs of bleeding are a reason to see a doctor without delay.

Do you pay attention to the results of your labors in the toilet?

It may not be very pleasant to look at your feces, except for a glimpse, or think about such an indelicate toilet topic. But this, nevertheless, the quality of bowel movements and the color of urine is a quick, simple and completely free way to understand if everything is in order with our body.

Source

Feces buoyancy linked to gut microbiota

American researchers have figured out why some feces sink in water while others float on the surface. According to experiments on mice, the composition of the intestinal microbiota is solely responsible for this. The report on the work is published in the journal Scientific Reports .

Feces 10-15 percent of people float on the surface of the water, and this is not associated with any pathological condition. Among people with functional bowel disorders, this proportion rises to about one in four. Historically, it was believed that the buoyancy of feces is due to the high content of fat in it, but in 19In 1972, Michael Levitt, a gastroenterologist from the University of Minnesota, and his student William Duane, in experiments with the stool of 39 people (including six patients with steatorrhea), showed that even fatty feces sink when gas is removed. The researchers did not specify the origin of the gas component, and this question, which has the potential for clinical application, has remained open until now.

To understand it, staff at the Mayo Clinic in Rochester, Minnesota, under the direction of Nagarajan Kannan, used conventional C57BL/6 (B6) and gnotobiotic (born and reared in aseptic conditions that do not have a microbiome) mice. Some of the latter have been colonized with microbiota in their intestines by a single intragastric injection of the drug, either in the faeces of normal mice or one of two healthy women, or by allowing contact with environmental bacteria. Fecal sterility of germ-free mice and successful colonization of the intestines of the rest were confirmed by polymerase chain reaction, scanning electron microscopy, and measurement of bacterial DNA concentration (a measure of microbiota density).

Flow cytometry showed that the number of undigested particles of food biomass is inversely related to the density of the intestinal microbiota. In thermogravimetry, the feces of germ-free mice differed from the rest of the samples in at least three temperature ranges; pycnometry revealed its significant superiority in relative density. The shape, size and color of the stool in all groups of animals did not differ.

To assess the buoyancy of faeces, the researchers used a simple LIFT test they had previously developed – levô in fimo (literally translated from Latin as “raising in dung”) test. It consists in placing stool fragments in water and a Trump fixer solution (10 percent formaldehyde and one percent glutaraldehyde) in phosphate buffer (TFS), followed by recording their position (at the bottom or surface) after a minute, hour and day. It turned out that all samples from germ-free mice sink in water and TFS in less than a minute, while about half of the bacteria-colonized samples remain on the surface of the water and all of them continue to swim in TFS after a day.

Also, the authors of the work performed simultaneously LIFT and microbiota density determination in gnotobiotic mice before intragastric colonization (all faeces were drowned, bacterial DNA was practically not determined) and after it weekly for 12 weeks. By the third week, with all methods of microbiota formation (transplantation from mice and humans, from a non-sterile environment), the DNA concentration in the whole stool began to stabilize at a level of more than 10 thousand nanograms per milligram, from that time all biosamples floated.

Metagenomic analysis of the intestinal microbiota of conventional, artificially colonized gnotobiotic and their donor mice revealed 13 dominant species of gasogenic bacteria from 11 genera, and their composition in different animals was extremely heterogeneous. The most common was methane-producing Bacteroides ovatus , associated, as previously shown, with an increased risk of flatulence in humans.

Thus, the buoyancy of feces depends solely on the gases produced by the microbiota; Swallowed air and the chemical composition of the dense matter of the stool do not play a role in this, Kannan concluded.

In 2019, Tufts University researchers reported that transplanting feces from physically fit older adults significantly increased the grip strength of mice.