Common sweeteners can disrupt gut bacteria, especially with medications, Cambridge study finds

Cambridge researchers showed in vitro that common sweeteners slow growth of several gut bacteria; most notably, the isosteviol–duloxetine combination strongly suppressed Roseburia intestinalis and Parabacteroides merdae, reducing microbial diversity and altering interactions with host cells. The team tested 25 bacterial species against 39 sweeteners and examined interactions with substances like caffeine, vanillin, and eight drugs, uncovering over 100 interaction effects. Although the findings suggest that sweeteners can affect gut microbes—especially when mixed with other compounds—these were lab experiments and real-world health implications require further study.