<p><em>Researchers from China monitored 25 obese patients losing weight during and after intermittent energy restriction (IER) for changes in their gut bacteria and in brain regions for appetite and addiction. They showed that changes in both these compartments of the brain-gut-microbiome axis are tightly coupled in time. These results suggest that these changes could be linked by an as yet unknown mechanism: either changes in the gut microbiome drive changes in the brain or vice versa.</em></p>