Body and Brain
When a dieter starves themselves of calories, they starve their brain cells as well. New research finds that these hungry brain cells then release "feed me" signals, which drive hunger, slow metabolism and may cause diets to fail.
When the researchers created mice whose brain cells couldn't send out the signals, or appetite-increasing proteins, and these mice were leaner and ate less than normal after being starved.
"We generated a mouse that lacked this process in these neurons," study researcher Rajat Singh, of Albert Einstein College of Medicine in the Bronx, New York, said. "What we find is these mice eat less in response to a starvation challenge; they are leaner and they are healthier."
The results likely would apply to humans, as mice are often used as biological models for us, the researchers say; even so, further research is needed to confirm the same process occurs in humans. [ 7 Diet Tricks that Really Work ]
Starving the brain
The starvation mechanism and feelings of hunger produced by these neurons is signaled through a process called autophagy, (which literally means "self-eating") in which the cell breaks down its used parts. They do this to recycle the used parts, but also to harvest energy from them.
Most brain cells keep their autophagy at a steady level and don't respond to starvation. These appetite-sensing neurons are different, the researchers found, and are now the only known brain cells to ramp up autophagy in times of starvation.