A new study from the Patil Lab, led by Sonja Blasche and Vinita Periwal and published in Molecular Systems Biology, reports on interactions between 25 phylogenetically diverse gut bacterial strains and 39 commercially used sweeteners. Three-quarters of the tested sweeteners individually impacted the growth of at least one tested bacterial strain. The most striking result was the combination of a sweetener called isosteviol, widely used in the food and beverage industry, and the antidepressant duloxetine. This combination strongly suppressed Roseburia intestinalis and Parabacteroides merdae, two gut bacteria that play important roles in maintaining a healthy digestive system.
Professor Kiran Patil said: ‘Our study suggests that artificial sweeteners don’t just pass through the body passively — they can interact with gut microbes, and these effects can be amplified or altered by other substances like medications. These findings can help guide new studies towards understanding how sweeteners might influence health in unexpected ways.’
Read a University feature article: ‘Sweeteners shown to slow growth of important gut bacteria in lab tests’
Read the paper: ‘Common xenobiotics modulate gut microbial responses to low‑calorie sweeteners in vitro’