A new study from the University of Oxford shows that the physiological need for sleep arises from an energy imbalance in brain cells.
Mitochondria, the organelles that convert oxygen and nutrients into energy, play a key role. When they become overloaded, an electron leakage begins, leading to the formation of reactive oxygen species—harmful molecules that signal to the body that it needs to sleep.
Experiments on fruit flies showed that certain neurons function as “circuit breakers,” reacting to excessive electron leakage and putting the body into sleep mode. By manipulating the flow of electrons, scientists were able to control the duration of rest. Replacing electrons with light energy using special proteins produced a similar effect.
According to the researchers, this discovery explains the connection between sleep, metabolism, and longevity: more active energy processes require more sleep, and mitochondrial dysfunction can lead to chronic fatigue. Thus, sleep serves not only a psychological but also an energetic protective function, supporting the brain’s vitality and longevity.
