Many of us probably spend sleepless nights from time to time. Some of us have even worse sleeping habits. Habits like not sleeping at nights, having to work at night can cause bad results for our hormonal systems. Just one of the reasons of these effects is night hunger...
Okay, even if it's sometimes because of extreme reasons or if it's a habit, you probably have noticed that we get more hungry at night times. What could be the reasons for the desire to eat food at midnight?
Actually, there is an answer to this question in the endocrine system; Ghrelin hormone, or with its common name hunger hormone...
Now, let's get to know the Ghrelin hormone in its general details
It's a hormone in the form of polypeptide that is secreted by the stomach by endocrine cells. While most of it is secreted by the stomach, it is known that it can also be secreted in small quantities by other organs of the body like pancreas, heart, kidney, and livers. It has a structure made up of 28 amino acids and it has an acylated ghrelin and deacylated ghrelin form according to whether or not a fatty acid has bonded with the 3rd amino acid or not
Main functions of acylated ghrelin: Exciting the growth hormone, balance of energy, nutrient consumption, and weight control.
Besides, the word Ghrelin comes from the combination of the words Ghre, which means grow and relin which means to secrete.
Mechanism affecting nutrient consumption:
Actually, there are three endocrine secretion hormones responsible for nutrient consumption together with Ghrelin, those are leptin and insulin hormones. They play an important role in our nutrition and the functions of these three hormones are as complementary cycles to each other.
The role of Ghrelin in this cycle is: appetizing and sending our brain the signal that we need to eat something.
Ghrelin's effect on appetite can show itself in different ways. The hormone that is synthesized in the stomach passes through the blood-brain barrier and affects the appetite at the hypothalamus level.
Apart from this, peripherally-synthesized Ghrelin excites the vagal afferent nerve tips and this causes GHS-R expression and by this, it excites the hypothalamus through the nucleus 69 solitarius which has a vagal connection.
The Ghrelin hormone and sleep
Sleep; It is a process consisting of Non-REM and REM phases.
The EEG shapes of REM sleep is similar to the state of being awake which shows a high frequency and low voltage waveform. NREM and REM sleep consists of about 90-minute cycles in a night. In the first half of the night, the NREM sleep will be dominant and in the second half REM will be dominant. The role of sleep on endocrine and metabolic functions have been known for many years. And the duration of the sleep has a direct effect on these functions.
Ghrelin shows that it serves as a sleep-enhancing factor by exciting slow wave sleep(SWS) and growth hormone that is secreted at night. While the level of Ghrelin is high throughout the sleeping period, it stars to decrease in the morning, a few hours before breakfast. Ghrelin level being at irregular levels excites increasing of hunger during sleep.
At that point, in irregular sleep, not only does the Ghrelin secretion gets negatively affected, but at the same time, the secretion of leptin gets negatively affected too. And as a result of this irregularity, problems that can that can get as serious as obesity might emerge.
Lastly, the benefits and usefulness of commonly known old diet methods such as eat less and frequently, doesn't seem to be a good solution when we think about the leptin & ghrelin hormone mechanisms.
If we take into consideration that the Ghrelin hormone is secreted every half an hour, we need to have long durations in between each meal and to not interrupt the secretion of leptin between two meals we need not to even chew gum. At the same time, getting over the feeling of hunger that Ghrelin creates, usually in sleepless nights by drinking water instead of eating something is a good way out. But the most logical solution is to have regulated sleep. I think that having a consistent sleeping habit that is sleeping at the same time every day and about 7 hours a day will be helpful for us about this...
The information on this post is provided for educational and informational purposes only.
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