To Eat or Not to Eat? That Is the Question!

Abstract

What is hunger? How do we know how much to eat? And what happens if we do not eat enough? To survive, the human body must have energy reserves available in the form of body fat. Using a hormone called leptin, the fat tissue regularly sends messages to the brain about the body’s energy reserves. When the brain receives a lot of leptin, it tells the body, “you are full, stop eating.” In certain situations, like obesity and pregnancy, the brain is less sensitive to leptin—so people do not feel full and they keep eating. We hypothesize that obesity and pregnancy change the blood vessels that transport leptin to the brain. As a result, an “illusion” of low energy reserves is created in the body, causing the brain to send fewer “stop eating” commands. As a result, people keep eating and gain weight.