THE BODY FAT SET POINT THEORY
This theory explains that we have a group of hormones that regulates appetite and body fat storage. These hormones communicate with one another and need to be in balance in order for us to achieve and maintain a healthy weight.
"All of these hormones must be doing their jobs and working in sync in order for us to achieve an optimal weight."
The important hormones are leptin, insulin, glucagon, ghrelin, and adrenaline:
Leptin was discovered in 1992 and has been found to control how much body fat we store, as well as when we are satiated.
Insulin is our main fat storage hormone.
Glucagon is the opposite of insulin. It stimulates the liver to release stored glycogen and works with adrenaline to free up our stored fats to use as energy.
Ghrelin tells us when we are hungry.
All of these hormones must be doing their jobs and working in sync in order for us to achieve an optimal weight. Other important factors include other peptides and even certain brain regions.
Leptin, Ghrelin, and Insulin
Leptin may just be the ringleader of this circus, though. Leptin is primarily secreted by our fat cells, and when levels are high, then our hunger is decreased. Ghrelin was discovered almost a decade after leptin and it controls our short-term hunger response. Ghrelin is released from the stomach lining, and when levels are high, we increase our hunger response. Both of these hormones are found to be in dysregulation during obesity.
Insulin has been a big focus of obesity research for quite some time. It is one reason why some people swear low-carbohydrate diets are the way to go. Insulin has a direct effect on leptin. As insulin levels rise, so do leptin levels. In fact, leptin receptors have been found on the beta cells of the pancreas, where insulin is produced. The problem is we can develop resistance to these hormones and this can cause a number of issues for us.
Developing Resistance to the Hunger Hormones
When we develop resistance to these hunger-controlling hormones, it is like our body is making a phone call, but we’re not picking up on the other end. As a result, our body needs to yell louder. It does this by releasing more and more of the hormones in question.
Let’s look at this scenario in terms of letpin. If we develop leptin resistance, it means more fat being stored and more food being eaten. Due to the relationship with insulin, if we have leptin resistance, then we have insulin resistance, too.
So, we get ourselves into this mess and then decide we need to get our weight in check. We count out our calories and subtract 500 calories per day, just as we have been taught. But in response to this low-calorie eating our body causes our leptin levels to fall. This, again, will increase our eating and fat storage.
"Due to the relationship with insulin, if we have leptin resistance, then we have insulin resistance, too."
On top of that, calorie counting does not take into effect how certain foods react with these hormones. We are told to approach everything in moderation, including our eating, but does this strategy work? Highly palatable foods have been shown to blunt both leptin and ghrelin. This is why it is easy to overeat foods such as ice cream and pizza. This can cause you to take in more calories than you even realize.