Scientists may have found the key to controlling hunger, by using lasers to control different parts of the brain.
The technique, which was trialled on mice, uses light to disrupt cells that send hunger messages.
By activating and deactivating the relevant neurons, scientists were able to induce hunger pangs, making the mice 'ravenous', and suppress appetite, causing mice to become disinterested in food even if they hadn't eaten for some time.
"This is a really important missing piece of the puzzle," neuroscientist Seth Blackshaw told Science News. "These are cell types that weren’t even predicted to exist."
Researchers, led by Joshua Jennings and Garret Stuber of University of North Carolina, said: "The growing prevalence of overeating disorders is a key contributor to the worldwide obesity epidemic. Dysfunction of particular neural circuits may trigger deviations from adaptive feeding behaviours."
The findings reveal the connections in the brain that drive hunger pangs and consumption of food, they added, regardless of whether energy needs have been satisfied. Interrupting these connections stopped feeding altogether.