Sucralose and stevia alter gut microbiome and gene activity across generations in mice
A mouse study finds both zero-calorie sweeteners changed gut bacteria, reduced beneficial metabolites, and shifted metabolic gene expression — with some effects detectable in offspring that never consumed them.
Researchers have found that two widely used zero-calorie sweeteners — sucralose and stevia — can alter the gut microbiome, reduce the output of beneficial bacterial metabolites, and change the activity of genes involved in metabolism and inflammation in mice. Notably, some of these changes were also detected in subsequent generations of animals that had never themselves been exposed to either compound, raising questions about possible transgenerational epigenetic effects.
The findings, reported via ScienceDaily from an as-yet unspecified primary publication, add to a growing body of research examining whether non-nutritive sweeteners have biological consequences beyond the gastrointestinal tract. Prior work has produced mixed results; this study is notable for its multigenerational design, though the authors and independent commentators caution that mouse gut physiology differs substantially from human gut physiology and that direct extrapolation is premature.
The mechanisms proposed centre on microbiome-mediated changes in short-chain fatty acid and other metabolite production, which in turn may influence epigenetic marks transmissible to offspring. The relative contributions of germline epigenetic inheritance versus shared maternal microbiome transfer to pups remain to be disentangled. Researchers and educators interested in transgenerational inheritance, diet–microbiome interactions, or epigenetic programming will find the conceptual framework of interest, while the preliminary and animal-model nature of the data warrants scrutiny before conclusions are drawn about human relevance.
Plain-language version
For patients, families, and general readers. Educational only — not medical advice.
Scientists studying mice have found that two common zero-calorie sweeteners — sucralose (found in some diet drinks and foods) and stevia — may do more than just sweeten food. In the mice studied, both sweeteners changed the mix of bacteria living in the gut, reduced the production of helpful substances those bacteria normally make, and altered how certain genes behaved. Perhaps most surprisingly, some of these changes were also found in the next generation of mice that had never eaten the sweeteners at all.
It is important to know that this research was done in mice, not people. How mice digest and respond to sweeteners is not the same as how humans do, so it would be wrong to draw firm conclusions about what this means for people. Scientists will need to do much more research before anyone can say whether these findings apply to humans. This is an educational summary, not medical advice. If anything here raises questions for you, please speak with your GP or a clinical professional.
Sources
Read the original reporting — these are the public sources this summary draws from.
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Primary source ScienceDaily · 2026-08-31Popular sweeteners may leave effects that last for generations