Going to the bathroom is essential, but is there an optimal number of trips to the toilet per day?
According to a new study published Tuesday, the frequency of bowel movements does indeed significantly influence long-term health. And their optimal number has been scientifically determined: once or twice a day.
Previous work has linked constipation to infections, and diarrhea to neurodegenerative diseases. But because these observations were made in sick patients, it is difficult to determine whether irregular trips to the bathroom were the cause or the consequence of these diseases.
Sean Gibbons, lead author of the new study published in the journal Cell Reports Medicine, said he hopes it "opens the minds of health professionals a little bit about the potential risks of poor stool frequency management." Too often, doctors dismiss irregular bowel movements as a mere "nuisance," he told AFP.
He and his team collected clinical and lifestyle data from 1,400 healthy adults, including blood samples, genetic information and information about their gut microbiome.
Participants self-reported their average stool frequency, and were categorized into four groups: constipation (one to two times per week); low normal (three to six times per week); high normal (one to three times per day); and diarrhea.
When stool remains in the intestine too long, microbes deplete the available fiber and begin to ferment the proteins, producing toxins.
"What we found is that even in healthy people who are constipated, there is an increase in these toxins in the bloodstream," Gibbons said.
In the case of diarrhea, researchers have found chemical indications of inflammation and liver damage. In this case, the body secretes excess bile acid.
– Fruits and vegetables –
People who defecated (largely) once or twice a day had more beneficial gut bacteria, the study found. Known as strict anaerobic bacteria, these ferment fiber.
Demographically, younger people, women, and people with lower body mass index tended to have fewer bowel movements.
Hormonal and neurological differences between men and women may partly explain these differences, the researcher said, as well as the fact that men generally eat more.
By combining biological and lifestyle information, the researchers also sought to determine which habits the participants appeared to be in better health had.
"Eating more fruits and vegetables is the most important signal we've seen," says Gibbons. As are drinking plenty of water and exercising regularly.
The next step, the researcher says, might be to design a clinical trial that looks at the frequency of bowel movements in a large number of people, and then follows them over a long period of time to see if they develop disease.
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