Scientists have discovered a “switch” in the brain to control hunger and promote feelings of satiety. The hypothalamus, which produces hormones and controls hunger among many other functions, expresses a receptor known as MC4R. MC4R then communicates with an area in the back of the brain to create a feeling of fullness.

Scientists altered the MC4R neurons in the brains of mice so they could be turned on or off with drugs. Hungry mice stopped eating when the MC4R was activated. They then altered the area to be turned off or on via light. Again the hungry mice preferred the area of light that promoted the satiated feeling. So maybe the next time I open my fridge and the light comes on I won’t be hungry? Not quite yet, but dieting sure would be easier that way!