* GHRELIN, the appetite increaser, is released primarily in the stomach and is thought to signal hunger to the brain. You’d expect the body to increase ghrelin if a person is undereating and decrease it if he or she is overeating. Sure enough, ghrelin levels have been found to increase in children with anorexia nervosa and decrease in children who are obese.
German researchers have suggested that ghrelin levels play a big role in determining how quickly hunger comes back after we eat. Normally, ghrelin levels go up dramatically before you eat; this signals hunger. They then go down for about three hours after the meal.
* LEPTIN — the appetite suppressor — appears to be the bigger player in our bodies’ energy balance. Some researchers think that leptin helps regulate ghrelin.
Leptin helps signal the brain that the body has enough energy stores such as body fat. But many obese people don’t respond to leptin’s signals even though they have higher levels of leptin.
In general, the more fat you have, the more leptin is in your blood. But the level varies depending on many factors, including when you last ate and your sleep patterns.
