Stevia and sucralose altered gut bacteria and gene activity in mice and their grandchildren, even though only the original generation consumed the sweeteners.
Sucralose left stronger and longer-lasting traces than stevia
Researchers gave 47 mice either water or a solution containing stevia or sucralose from adolescence, at doses matching typical human consumption. The mice were then bred over two generations, with only the founder generation exposed to sweeteners; offspring and grandchildren drank plain water. When all animals reached adulthood, scientists analyzed their gut flora, glucose tolerance, and epigenetic changes in five key genes regulating inflammation, gut barrier function, and liver and intestinal metabolism.
Changes persisted in grandchildren despite no direct exposure
The founder mice showed expected shifts, but their children and grandchildren also exhibited altered gut bacteria and gene activity. Offspring produced fewer health-promoting short-chain fatty acids, and grandchildren of sucralose-exposed mice had more disease-associated and fewer beneficial bacteria in their stool. In gene activity, proinflammatory genes Tlr4 and Tnf were more active in descendants, while expression of certain metabolism genes decreased. These effects were strongest in the first offspring generation and diminished in the grandchildren, with sucralose showing more pronounced and enduring impacts than stevia.
Researchers caution against direct human extrapolation
The observed changes were subtle shifts in how the body regulates glucose and genes linked to inflammation and metabolism, not proof that sweeteners cause metabolic disorders. Still, such alterations could increase susceptibility to these conditions under specific circumstances, like a high-fat diet. The findings suggest sweetener-induced changes might be transmitted across generations via epigenetic DNA markers, a mechanism already shown for diet-related patterns. Whether these results apply to humans remains uncertain and requires further study, as noted by lead researcher Concha Celume and independent physiologist Parveen Yaqoob of the University of Reading.
Could these effects occur in humans at typical sweetener intake levels?
The study used doses equivalent to average human consumption, but researchers say more research is needed to determine if similar transgenerational effects occur in people.
Does this mean stevia and sucralose are unsafe?
No, the researchers emphasize that the observed changes do not prove sweeteners cause metabolic disorders, only that they may increase vulnerability under certain conditions.
