Regular coffee consumption is associated with greater gut microbiome diversity, lower small intestine acidity, and increased colon contractions, according to a scientific study published on November 14, 2026, by researchers at the Euronews network. The research, carried out by a team at the University of Copenhagen and published in the journal “Gut Microbiology”, examined the physiological conditions inside the human digestive system relative to habitual coffee intake.
The study involved 61 healthy adults in Denmark divided into two groups based on their consumption habits. The first group consisted of individuals drinking between one and five cups of coffee daily on more than three of the eight days monitored, while the second group drank coffee less frequently. To track internal changes, participants swallowed a small electronic capsule that measured gastrointestinal transit time, temperature, acidity levels, and intestinal contractions as it passed through the digestive tract.
Physiological Findings and Intestinal Activity
The results showed that participants who consumed coffee regularly exhibited greater diversity in their intestinal microorganisms compared to the less frequent coffee drinkers. Additionally, regular coffee drinkers recorded significantly lower acidity levels in the small intestine. Researchers also observed a link between higher coffee intake and an increased frequency of colon contractions, which are muscle movements that help push waste along the digestive tract.
Francesca Bucci, lead researcher and a PhD student in the Department of Nutrition, Exercise and Sports at the University of Copenhagen, noted that these regular contractions can support proper digestion, help reduce constipation, and maintain the functional state of intestinal muscles. However, the research team stated they are still unable to determine whether the lower level of small intestine acidity provides a direct health benefit or could result in negative effects.
Causation Questions and Next Steps
While the study demonstrates correlations between coffee consumption and digestive shifts, researchers emphasize that it cannot definitively prove that coffee is the direct cause of these changes. Henrik Munch Roager, associate professor and head of the research group at the University of Copenhagen’s Department of Nutrition, Exercise and Sports, pointed out that previous research shows coffee affects stomach acid secretion and other digestive processes, making it likely that the observed differences are linked to coffee rather than mere coincidence.
To establish direct causation, the research team plans to conduct a controlled trial where participants’ coffee intake is strictly regulated, moving beyond observational comparisons. This upcoming methodology aims to clarify the precise mechanisms through which coffee influences bowel movements and intestinal contractions.