Our bodies are extremely clever in appetite and weight regulating. Our bodies try to keep things the same (maintain Homeostasis). If we decide to go down the diet path, (less food than needed), our bodies will start revving up our appetite hormones,
We have different hormones produced in our bodies that will signal us when it time to eat and when we are full.
Two hormones that affect our appetite are Ghrelin and Leptin:
Ghrelin is called the “Hunger Hormone” It tells us when we are hungry. It is a peptide released by the small intestine (mostly in the lining of the stomach) before we start injesting food, meaning it is a appetite regulator. Ghrelin levels rise before a meal and fall after your finished. Ghrelin also plays a role in regulating the distribution and the rate of use of energy. An over production of this hormone can cause Prader-Willi Syndrome. Ghrelin also tends to be lower in the elderly, this is one of the reasons they don’t seem to get hungry.
Leptin is produce in fat tissue so the more fat tissue you have the more leptin in produced. What tends to happen in obesity is that the brain isn’t listening to your leptin levels and sends the signal that your even hungrier. (the signal is disrupted). There is even research out there showing that fructose can induce leptin resistance.
Other hormones that affect appetite are:
Dopamine is called the feel good neurotransmitter. This hormone is required to initiate feeding, it also stimulates our reward system.
Neuropeptide Y is a hormone that is released by our bodies in the morning. This hormones turns on our want for carbohydrate rich foods. If we skip meals this hormone will heighten our need for carbohydrates. It is turned of by serotonin and is revved up by cortisol production (stress hormone).
Galanin is a hormone that increases its levels in the afternoon and evening. It is stimulated by burning fat as fuel.
Cortisol is call our stress hormone. This is the hormone that releases glucose so that the body can use it as energy. This hormone has a impact on our insulin sensitivity and resistance. Cortisol stimulates Neuropeptide Y (the hormone that turns on our wanting for carbohydrates). If we remain is a high stressed state, cortisol remains high in our systems which has many negative side affects in our bodies. In a healthy body, cortisol levels fall in the evening and melatonin levels begin to rise, this is another reason that we should be turning off over-stimulating devises at night.
Cholecystokinin (CCK) is a hormone that starts to be released when we start eating. This hormone makes us feel full, but can take around 20mins for this affect to be felt. This is why it is important for us to eat slowly so that we don’t over eat. (remember put your knife and fork down between every mouthful).
Insulin is a energy storing hormone. Think of insulin as a key that unlocks the cells so that they can transport glucose into the cell to be stored as energy. If there is to much sugar in your blood and it cant be stored in your cells, insulin will transport it to your liver to be stored as fat which can result in Hypoglycemia.
By understanding are hormones we are in a far greater place to reach full happiness and health.