The frequency of bowel movements reveals important indicators related to gut health and the balance of bacteria in the gut, something scientists have begun to understand more deeply in recent years.
One study suggests that bowel movement frequency is not only linked to digestion but may also directly influence the composition of the gut microbiome. The gut microbiome refers to the community of microorganisms—including bacteria—that aid in food digestion and nutrient absorption, while simultaneously producing compounds that may affect overall health.
A team of researchers, led by food scientist Hakdong Shin from Sejong University in South Korea, analyzed the gut microbiome of 20 people, who were divided into three groups according to the frequency of their bowel movements: those who have a few bowel movements per week, those with a moderate frequency, and others who have a bowel movement daily.
By analyzing stool samples using advanced techniques, the team observed clear differences in the composition of the microbiome between these groups. It was found that people who defecate less frequently have a greater diversity of bacteria in their gut compared to those who defecate daily.
Differences in the type of bacteria were also observed; bacteria such as *Ruminococcus* were more common in those with less frequent bowel movements, while *Bacteroides* was more prevalent in those with daily bowel movements. Previous animal studies suggest that this latter type may be associated with reduced weight gain, given its role in breaking down compounds linked to obesity.
The results indicate that the duration of fecal matter in the colon plays a significant role; the longer it remains, the greater the opportunity for bacteria to ferment its contents and produce compounds that may affect the gut microbiome and overall health. This creates a kind of "feedback loop" between defecation and the microbiome.
This effect is also linked to diet; protein-rich foods take longer to digest, prompting the body to promote the growth of certain types of bacteria specialized in breaking them down. Over time, these bacteria may alter the gut environment through their metabolic byproducts.
Despite these results, researchers emphasize that the relationship is complex, as the frequency of defecation is affected by multiple factors such as food, water intake, physical activity, and sleep.
This study supports the findings of other research, including a study of more than 1,400 people, which showed that regular bowel movements of once or twice a day are associated with better health compared to irregular patterns.
Evidence also suggests that slow bowel movements and constipation may be linked to health problems such as metabolic disorders, inflammation, and even neurological diseases like Parkinson's. Additionally, certain compounds produced during protein digestion—such as indole and para-cresol—may contribute to an increased risk of kidney and heart disease.
While these results appear promising, the researchers point out that the study is small in number, and that the gut microbiome is constantly changing, which calls for broader and more accurate studies to better understand this relationship.
