Ghrelin is your primary hunger hormone. It is released from your stomach lining when you are hungry. It then circulates through your blood to your brain to alert you to your physical hunger. It has many functions throughout your body besides hunger. It also functions within the pleasure/reward center of the brain, plays a role in memory formation, immune function, and even sleep.
A Answers (4)
Marjorie Nolan Cohn, Nutrition & Dietetics, answered on behalf of Academy of Nutrition and Dietetics
Our bodies secrete a hormone called ghrelin, which controls our hunger and drives our appetite. If we do not understand, monitor, and control our ghrelin, we can forget about losing weight.
Here's what we know about ghrelin today. It's a hormone secreted in the stomach when we are hungry. It is also known to increase appetite, so while the body is asking for food (and we are often denying it), ghrelin strategically triggers appetite in the brain. Why? Because we've trained ourselves to ignore a rumbling tummy, but once our brains get into the act, with our powerful imaginations fueling our appetite, it's far harder to resist food. We're dreaming of bagels, cheeseburgers, ice cream, and pizza. Never underestimate the power of the appetite to tempt us. It's an incredibly formidable foe.
Here we are, hungry, stomach growling, headache setting in, and our mood deteriorating by the minute. Our ghrelin is working hard, simultaneously increasing our appetite since we choose to ignore our physical hunger. What else is the ghrelin doing at this stage? It's decreasing our metabolism and our ability to burn fat. This is happening because the body is receiving signals that it's not going to be fed. In response, it begins to slow its processes and hang on to whatever stores of energy and fuel it's already got. While we're starving and fighting the hunger we feel, and dreaming of cheeseburgers, we're cueing our bodies to hold on to fat and to stop metabolizing what we've already eaten. Surely, this defeats the purpose of starving ourselves in the first place! The harder we try to avoid eating, the more desperately we want food, and meanwhile, our bodies are hanging on to fat and shutting down processing functions. Think of all of the people on diets who congratulate themselves for their incredible willpower while they're actually telling their bodies to hang on to that extra weight, just as their brains are preparing for an epic binge sometime in the near future.
I like to think of ghrelin as a little gremlin: a monster that lives inside us all. It needs to be fed constantly, at a slow, steady pace. When we ignore it or starve it, the gremlin goes out of control and begins fighting back. While you may hold tough for a while, eventually you are powerless against it. Hello, late-night binge!
Find out more about this book:Eating Free: The Carb-Friendly Way to Lose Inches, Embrace Your Hunger, and Keep Weight Off for Good
Discovery Health answered
Ghrelin is a hormone that tells your brain that you're hungry. When you don't sleep well, more of this hormone is produced, causing your brain to keep getting the message that you need to eat. That's why researchers link obesity to sleep deficiency
Eliot LeBow, CDE, LCSW, Endocrinology, Diabetes & Metabolism, answered
Ghrelin is a hormone that gets released by the stomach to communicate the message to the brain that it is time to eat. At that point, the hypothalamus section of the brain releases neuropeptides, which trigger hunger. This part of hunger is a type of biochemical reaction that allows a person to desire or crave for food.