What is ghrelin and how does it work?
When the hormone ghrelin is released, signals are sent to the brain for a person to feel the need to eat. In many obese patients, ghrelin secretion levels are altered, consequently making them feel a greater need to eat than they should actually eat. These individuals eat large portions of meals in order to experience a sense of satiety.
Ghrelin levels are increased before food is consumed and then decrease in proportion to the amount of calories consumed. The level of the hormone increases when a person is on a reduction diet with improperly composed meals. Ghrelin plays a very important role in the long-term regulation of body weight, as patients often do not feel satiated which makes it difficult to maintain an eating regime for a long period of time.
How does ghrelin affect weight gain?
Ghrelin is produced when the stomach is empty and during periods of negative energy balance, such as low-calorie diets, chronic exercise or anorexia nervosa. This partly explains why a person who goes "on a diet" feels hungry. The concentration of ghrelin increases before meals, stimulating the feeling of appetite, and decreases after eating.
How does surgery affect ghrelin?
Sleeve gastrectomy is a procedure that aims to reduce the size of food portions. During the operation, the part of the stomach most active hormonally, responsible for the production of ghrelin, is removed. After sleeve gastrectomy surgery, the patient has less appetite and the feeling of satiety is obtained earlier and lasts longer. It has been found that ghrelin levels in the blood significantly decrease after gastric sleeve surgery, this decrease is observed from the first postoperative day and lasts up to 24 months.
What do patients really experience after sleeve gastrectomy surgery?
Given that each person is different and their experience can vary greatly. The most important thing is what the patient experiences in the post-operative period and based on the experience of our patients, we can summarise it as follows.
There are patients with a reduced stomach who immediately after surgery notice a significant change in the intensity of their hunger, in other words they don't feel an appetite for months, so they even have to set an alarm to remind them that it's time for one of their 4-5 meals a day.
On the other hand, there are patients (we could say the majority) who describe a different feeling of appetite compared to what they perceived before the operation, so they don't stop feeling hungry when several hours have passed without eating, but the feeling is no longer as intense and unpleasant, but simply tells them that it is time to eat something.
It allows them to be more aware, allows them to make the right food choices, to eat slowly and in the right amounts. It is also worth mentioning that in the early post-operative period, when patients start taking solid foods, many of them do not yet know the full capacity of their new stomach - portion size, texture or tolerance of products. These people often have not changed their relationship with food, so they may initially "overeat" which can then lead to nausea, vomiting, a feeling of congestion or chest pain. Overeating should be understood as the patient eating 5 or 6 bites of food instead of 4.
This process is learning to eat. And this is the key moment in making all possible efforts and changes not only in the quality and quantity of food, but also in the mental and emotional aspect. All with the aim of maintaining the weight loss over the years, because if the patient does not effectively use this valuable period of change, which lasts about 18 months, they can regain the weight they have lost.
