Epilepsy, one of the most common neurological disorders, is characterized by the spontaneous repetition of seizures caused by the hyperactivity of a group of neurons in the brain. Could we therefore reduce neuronal hyperactivity, and treat epilepsy, by reducing the amount of energy supplied to neurons and necessary for their proper functioning? This was tested by a team led by scientists from the University of Geneva (UNIGE) and the EPFL. The researchers discovered that, in mice, the seizures were actually exacerbated. They observed that a reduction in the amount of energy led to an increase in the level of calcium in neurons, making them hyperexcitable. These dysfunctions could be corrected when mice were fed a ketogenic diet, which is rich in lipids and has been used since antiquity. This work is published in the journal eLife.