Why did you know when your body is full?

Diposkan pada oleh Skeptical Inquirer

Hunger claws at your grumbling belly. It tugs at your intestines, which begin to writhe, aching to be fed. Being hungry generates a powerful, often unpleasant physical sensation
that’s almost impossible to ignore. After you’ve reacted by gorging on your morning pancakes, you start to experience an opposing force, fullness, but how does your body actually know when you’re full?
The sensation of fullness is set in motion as food moves from your mouth down your esophagus. Once it hits your stomach, it gradually fills the space. That causes the surrounding muscular wall to stretch, expanding slowly like a balloon. A multitude of nerves wrapped intricately around the stomach wall sense the stretching. They communicate with the vagus nerve up to the brainstem and hypothalamus, the main parts of the brain that control food intake. But that’s just one input your brain uses to sense fullness.
Hypothalamus-new.jpg
After all, if you fill your stomach with water, you won’t feel full for long. Your brain also takes into account chemical messengers in the form of hormones produced by endocrine cells throughout your digestive system. These respond to the presence of specific nutrients in your gut and bloodstream, which gradually increase as you digest your food. As the hormones seep out, they’re swept up by the blood and eventually reach the hypothalamus in the brain.
Over 20 gastrointestinal hormones are involved in moderating our appetites. One example is cholecystokinin, which is produced in response to food by cells in the upper small bowel. When it reached the hypothalamus, it causes a reduction in the feeling of reward you get when you eat food. When that occurs, the sense of being satiated starts to sink in and you stop eating. Cholecystokinin also slows down the movement of food from the stomach into the intestines. That makes your stomach stretch more over a period of time, allowing your body to register that you’re filling up. This seems to be why when you eat slowly, you actually feel fuller compared to when you consume your food at lightning speed.
Pictures-of-Cholecystokinin-1482.jpg
When you eat quickly, your body doesn’t have time to recognize the state it’s in. Once nutrients and gastrointestinal hormones are present in the blood, they trigger the pancreas to release insulin. Insulin stimulates the body’s fat cells to make another hormone called leptin. Leptin reacts with receptors on neuron populations in the hypothalamus.
ShowImage.ashx.jpg
The hypothalamus has two sets of neurons important for our feeling of hunger. One set produces the sensation of hunger by making and releasing certain proteins. The other set inhibits hunger through its own set of compounds. Leptin inhibits the hypothalamus neurons that drive food intake and stimulates the neurons that suppress it. By this point, your body has reached peak fullness. Through the constant exchange of information between hormones, the vagus nerve, the brainstem, and the different portions of hypothalamus, your brain gets the signal that you’ve eaten enough.
stock-vector-insulin-and-the-pancreas-in-the-role-of-glucose-metabolism-showing-the-effects-of-diabetes-670783486.jpg
Researchers have discovered that some foods produce more long-lasting fullness than others. For instance, boiled potatoes are ranked as some of the most hunger-satisfying foods, while croissants are particularly unsatisfying. In general, foods with more protein, fiber, and water tend to keep hunger at bay for longer. But feeling full won’t last forever. After a few hours, your gut and brain begin their conversation again. Your empty stomach produces other hormones, such as ghrelin, that increase the activity of the hunger-causing nerve cells in the hypothalamus. Eventually, the growling beast of hunger is reawakened. Luckily, there’s a dependable antidote for that.
gastric-leptin-and-the-feeling-of-fullness-after-metabolic-surgery-1-693x400.png

Tinggalkan komentar

Diterbitkan oleh Skeptical Inquirer

• Central For Inquiry (CFI) • Skeptical Inquirer • Free Inquiry • Point of Inquiry ------------------------------------------------------------ 1. Yang nyata ialah manusia itu sendiri bukan tuhan, bukan manusia pikiran tuhan, tetapi tuhan adalah pikiran manusia, agama tidak merubah kenyataan dan mengukir sejarah, tetapi manusia itu sendiri yang merubah dan mengukirnya. Bukan tuhan yang menciptakan manusia tetapi tuhan adalah angan-angan manusia. Agama tidak merubah kenyataan tetapi menusia bisa merubah kenyataan. 2. Agama ialah proyeksi manusia : tuhan, neraka, surga, malaikat. Kenapa? Karena manusia butuh tempat untuk mencurahkan keluhan karena dunia tanpa hati, jadi penderitaan tempat lahirnya tuhan. Dengan demikian agama disebut keterasingan manusia dari kehidupan karena struktur masyarakat tidak mengizinkan secara penuh perealisasian diri sendiri, sehingga manusia membangun kerajaan angan-angan (agama). Dalam kenyataan manusia menderita lalu ia mengharapkan surga 3. kenapa agama khayalan, karena agama tidak inderawi, sedangkan manusia inderawi, manusia penuh dengan kepastian sedangkan agama berbau unsur spekulatif, unsur yang tidak bisa diterima secara ilmiah 4. Jadi agama dan tuhan ialah ciptaan manusia itu sendiri, tetapi manusia itu sendiri lupa dengan ciptaanya (seperti pada zaman jahiliyah dahulu sebelum nabi muhamad dating : orang-orang kafir zaman dahulu mengukir tuhan dari kayu dan batu, yang kemudian disembahnya, sama seperti kita kini yang memproyeksikan tuhan lalu menyembahnya). Agama penyembahan tuhan terhadap dirinya sendiri. Agama penyembahan manusia terhadap ciptaanya sendiri 5. Sehingga khayalan atau angan-angan itu mempunyai eksistensi realitas yang membuat manusia takut dan harus menyembahnya dan tuhan mempunyai hakikat lain yang manusia harus sembah. Sifat-sifat itu yang membuat manusia egois. 6. Penderitaan manusia ialah tempat lahirnya tuhan, penderitaan yang memaksa manusia mengasingkan diri ke dalam agama, itulah dasar yang menyebabkan manusia merasa butuh agama dan tuhan 7. Teologi harus diganti menjadi antropologi dan agama ialah candu rakyat. 8. Kritik agama hanya meruska bunga khayalan pada rantai, bukan bunganya yang harus dipatahkan tetapi rantai itu sendiri. Rantai (factor yang menyebabkan manusia mengasingkan diri ke dalam agama) 9. Kita seperti wayang dengan penuh kesadaran dan kemauan tetapi kita tidak bisa lepas dari tangan sang dalang. 10. Kalau semua ini benar, maka manusia bukan merealisasikan keinginanya tetapi mengharapkan berkah dariNYA (proyeksi manusia itu sendiri/perubahan pasif) 11. agama ialah keterbatasan: agama melarang kita bergaul dengan duniawi, sehingga kita hanya memikirkan surgawi Tanpa agama kita bisa hidup lebih baik, tanpa mengaharapkan hibah/welas asih dariNYA, hanya mengandalkan kenyataan dan diri sendiri. 12. Kepasrahan adalah kelemahan agama 13. Tuhan seperti halnya dengan setan, bila ia terus diyakini dengan adanya exsistensinya maka semakin berkuasalah ia, kita seperti member roh kepadanya dengan keyakinan kita. GROUP : https://www.facebook.com/groups/scientistsecularist