Frontiers in Nutrition: Sucralose and Stevia Altered the Gut Microbiome for Two Generations in Mice

Scientists have found that popular zero-calorie sweeteners may cause long-lasting changes in metabolism, with some of these effects persisting in offspring that were never exposed to the sweeteners themselves. The study was published in Frontiers in Nutrition.

Sweeteners such as sucralose and stevia are widely used as “healthier” alternatives to sugar because they contain little to no calories. However, a growing body of evidence suggests that they may not be as biologically neutral as commonly believed and, in particular, may affect the gut microbiome—the community of bacteria that plays an important role in digestion and metabolism.

Researchers led by Francisca Concha Selume of the University of Chile conducted an experiment involving 47 mice across three generations. Some animals were given sucralose, while others received stevia. The scientists then analyzed their gut microbiome, glucose tolerance, and gene activity, and tracked the effects in subsequent generations.

The researchers found that both sweeteners altered the gut microbiome and reduced levels of beneficial bacterial compounds, with sucralose producing stronger and more persistent effects than stevia. Most surprisingly, some changes in glucose tolerance and gene activity remained detectable in mice even two generations after the initial exposure, despite those offspring never receiving the sweeteners themselves.

The findings suggest that the effects of sweeteners could be passed on through changes in the gut microbiome or through epigenetic mechanisms.

“The goal of this study is not to cause panic, but to show that further research is needed,” said Francisca Concha Selume. The authors emphasize that the findings come from a mouse study and cannot be directly extrapolated to humans. However, they argue that the results warrant closer investigation of the long-term effects of artificial and plant-based sweeteners.