How Your Hunger-Satiety System Affects Your Physical Shape
Your hunger-satiety system consists of multiple neuro-peptides that act to initiate or terminate your food intake. These are your hunger-satiety hormones. Their signals are integrated by centers in your brain to modulate how you consume, spend or store energy. The balance between these signals dictates whether your body is in a fat-burning or a fat-storing mode.
In order to maintain a healthy body weight, your hunger and satiety signals must continually adjust your food feeding quantities to your energy expenditure. Any imbalance between these two will affect your fat stores and physical shape. The consequence of obesity, obviously is the result of a energy balance, gone astray, in which a surplus of accumulated food energy is stored as body fat.
The most important and well-known satiety hormones are insulin and leptin, but there are several others. In respect of hunger hormones, reported first in 1999, ghrelin has also drawn attention in recent years. Surely over the course of the next few years a lot of attention will be paid on important hormones and their impact on your health. Like it or not, those little things govern and rule the rest of our body (mainly) from our brain. It is really not your genes or DNA which simply are there and are rather "stable and immovable" except for some methylation processes as described in the preceding article "Epigenetics".