Even without decaf, the results were similar to tests with caffeinated coffee.
Coffee drinkers are well aware of the fact that coffee keeps the bowel moving. For years, it was believed that caffeine is the major ingredient behind this, however, a new study from Texas researchers deny those claims. A study published at Digestive Disease Week (DDW) 2019, showed that coffee suppressed gut bacteria and increased muscle motility in rats, regardless of the caffeine content. Xuan-Zheng Shi, who is an associate professor at the University of Texas Medical Branch, Galveston led the study.
She explained that a team of researchers fed the rats coffee and tested effects on gut bacteria in Petri dishes. “When rats were treated with coffee for three days, the ability of the muscles in the small intestine to contract appeared to increase,” said Xuan-Zheng Shi. Furthermore, he added saying, “Interestingly, these effects are caffeine-independent, because caffeine-free coffee had similar effects as regular coffee.” The study showed that the growth of bacteria and other microbes in fecal matter in a petri dish was suppressed with a solution of 1.5% of coffee. Moreover, this growth was even lower when it was treated 3% of the coffee solution.
In fact, decaffeinated coffee has a similar impact. The authors concluded saying, “in vitro and in vivo studies show that coffee stimulates intestinal smooth muscle contractility and inhibits gut microbiota in a caffeine independent manner.” The results of this study support the need for additional clinical research to determine, whether coffee drinking might be an effective treatment for post-operative constipation, or ileus, in which the intestines stop functioning after abdominal surgery.