Overweight • 29 with the hormone ghrelin, and the way your body lets you know you are full is with the hormone leptin. When they are working properly, you will feel hungry rarely and full often. But if you consume too much sugar and flour too often, they can't function properly. Ghrelin is signaled by the stomach lining. When it's empty for too long and not accessing fat for fuel, it sends the hunger signal to the brain. The problem with sugar and flour is that they are concentrated and don't fill the stomach the way they would if eaten as something naturally occurring. For example, one glass of apple juice is the equivalent of four apples. If you ate four apples, the ghrelin signal would stop, but when you drink a glass of juice the hunger signal is still very strong. The solution is simple. Implementing it is challenging, but the answer is so clearly this: Eliminate sugar and flour from your diet, eat less often and dine in more often.