To lose weight, it is estimated that 42 % of adults in the West[1] have already tried poor calories diets. The repetition of these diets, resulting in alternating reduction phases and then reugration from calorie intakes is often accompanied by a Yo-Yo effect: individuals are gaining more weight than they had lost. These repeated restrictions would deregulate eating behavior, promoting the appearance of disorders such as bulimic hyperphagia, associated with compulsive sockets of large quantities of food.
In this context, scientists from INRAE, CNRS, the University of Rennes and the Burgundy Europe University have looked at the microbiota track to understand its involvement in the disruptions of eating behavior.
They first shown, in mice, that the alternation of standard and fatty/sweet diets induced weight variations of Yo-Yo type and a modification of their eating behavior towards specific hyperphagia for fatty/sweet food.
Analysis of faecal samples has revealed a change in the microbiota in hyperphagic mice. Scientists transferred this microbiota to healthy mice. As a result, they have developed the same compulsive behavior towards fatty/sweet foods, which highlights the role of the microbiota in the disruption of eating behaviors.
Changes in the brain of mice have even been observed, with an increase in the expression of genes linked to the reward system, an area that contributes to food pleasure. Cellular changes have also been identified in the brainstem, a zone which incorporates information from the intestine.
These results confirm the potentially harmful effects on the health of restrictive restrictive regimes and underline the interest of taking into account the intestinal microbiota in the management of medically followed patients for weight loss. To confirm the potential applications of these first results, additional work in humans will be necessary, such as surveys of people subject to the Yo-Yo effects associated with composition analyzes of their microbiota.
[1] Santos I., Sniehotta F. F., Marques M. M., Carraça et al. (2017). Prevalence of personal weight control attempts in adults: a systematic review and meta-analysis. Obesity Reviews18, 32–50, two: 10.1111/obr.12466.
Reference
Fouesnard M., Salin A., Ribes S. et al. (2025). Weight cycling deregulates eating behavior in mice via the induction of durable gut dysbiosis. Advanced Science. DOI : http://doi.org/10.1002/advs.202501214