How Often You Poop Could Reveal Important Health Clues

“How often do you poop?” may seem like an intensely personal question, yet the answer can say a great deal about your general health.

A study published in 2024 examined how frequently people opened their bowels, comparing those figures with demographic, genetic and health information.

Among the 1,425 participants, the healthiest people said they pooped once or twice daily – the ‘Goldilocks zone’ for bowel movement frequency.

The team, led by researchers at the Institute for Systems Biology (ISB), found that going to the toilet either too frequently or too infrequently was linked with different underlying health problems.

“This study shows how bowel movement frequency can influence all body systems, and how aberrant bowel movement frequency may be an important risk factor in the development of chronic diseases,” said ISB microbiologist Sean Gibbons, the corresponding author of the report.

“These insights could inform strategies for managing bowel movement frequency, even in healthy populations, to optimize health and wellness.”

Watch the video below for a summary:

How the bowel movement frequency study was conducted

The research assessed the toilet habits of people considered “generally healthy”, meaning they had no history of kidney or gut conditions such as kidney disease, irritable bowel syndrome or Crohn’s disease.

Participants reported their own bowel movement frequency, after which researchers placed them into four groups:

• constipation: one or two bowel movements a week;
• low-normal: three to six movements a week;
• high-normal: one to three movements a day; and
• diarrhoea: four or more watery stools a day.

The researchers also assessed blood metabolites and blood chemistry, genetics, and the gut microbes found in participants’ stool samples. They then searched for potential relationships between bowel movement frequency and these health indicators, alongside factors including age and sex.

Overall, less frequent bowel movements were more commonly reported by women, younger people and those with a lower body mass index (BMI). However, even after allowing for these factors, the constipation and diarrhoea groups had distinct associations with underlying health concerns.

Bacteria more usually found in the upper gastrointestinal tract appeared more often in stool samples from participants with diarrhoea. Their blood samples also contained biomarkers linked to liver damage.

Constipation, gut microbes and protein fermentation

Stool samples from people who opened their bowels less often contained higher levels of bacteria associated with protein fermentation, a recognised risk of constipation.

“If stool sticks around too long in the gut, microbes use up all of the available dietary fiber, which they ferment into beneficial short-chain fatty acids,” said Johannes Johnson-Martinez, a bioengineer at ISB.

“After that, the ecosystem switches to fermentation of proteins, which produces several toxins that can make their way into the bloodstream.”

As expected, several of those by-products were detected in these participants’ blood samples. One that was particularly abundant was indoxyl-sulfate, a known product of protein fermentation that can harm the kidneys.

The researchers say this result may provide evidence of a causal connection between bowel movement frequency and overall health.

There is also some reason to think people may be able to alter their habits, and consequently their health. Recent research indicates that the gut microbiome can change far more quickly than might be expected.

For example, a 2025 German study followed inactive adults who started resistance training two or three times weekly. Participants who made the greatest strength gains experienced changes to the composition of their gut bacteria within only eight weeks.

Such changes could help certain people leave the constipation or diarrhoea groups and enter a healthier range of bowel movements.

The Goldilocks zone for bowel movements

People in the pooping Goldilocks zone said they ate more fibre, drank more water and exercised more regularly. Their stool samples also had high levels of bacteria linked with fibre fermentation.

A clinical trial published in 2025 by US researchers found that people whose guts contain many methane-producing microbes are particularly effective at converting dietary fibre into short-chain fatty acids.

This indicates that both fibre intake and the particular blend of microbes in a person’s gut matter. It also helps explain why two people following the same diet can have different health outcomes.

Naturally, everyone has been at one extreme or the other at some stage in life, whether after picking up a stomach bug or eating too much cheese.

However, this study considered people’s usual routines, showing that our individual idea of ‘normal’ may point to health concerns we did not know about.

The research was published in the journal Cell Reports Medicine.

An earlier version of this article was published in July 2025.