An ISB-led research team examined the clinical, lifestyle, and multi-omic data of more than 1,400 healthy adults.
The research team categorized self-reported bowel movement frequency into four groups: constipation (one or two bowel movements per week), low-normal (between three and six bowel movements per week), high-normal (between one and three bowel movements per day), and diarrhea.
Once categorized, the team looked for associations between bowel movement frequency and factors including demographics, genetics, gut microbiome, blood metabolites, and plasma chemistries.
The study showed that age, sex, and body mass index (BMI) were significantly associated with bowel movement frequency. Specifically, younger people, women, and those with a lower BMI tended to have less frequent bowel movements.
Specifically, microbially derived protein fermentation byproducts known to cause damage to the kidneys, like p-cresol-sulfate and indoxyl-sulfate, were enriched in the blood of individuals reporting constipation, while clinical chemistries associated with liver damage were elevated in individuals reporting diarrhea.
The study also explored associations between bowel movement frequency and anxiety and depression, indicating that mental health history is connected to how often one poops.
“Prior research has shown how bowel movement frequency can have a big impact on gut ecosystem function,” said Johannes Johnson-Martinez, the lead author of the study. “Specifically, 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. After that, the ecosystem switches to fermentation of proteins, which produces several toxins that can make their way into the bloodstream.”
