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Summary of the film

"The stomach - your second brain" 

(Le ventre notre deuxieme cerveau, France 2013)


The film "Belly - our second brain" was a great movie experience for me. A very well put together factual film with professionals in their field. Among many other excellent scientists, Michael Gershon, the author of the book "The Second Brain", will speak. The summary below gives a brief overview of the content of the film.



Introduction to the film

Scientists have discovered that there is another brain in our body, where billions of connected nerve cells and neurotransmitters transmit and carry out commands independent of the brain. It is nothing more than our stomach, which has been considered boring and passive in the past, but in the light of recent science is an important center that controls a powerful army of countless bacteria and also greatly influences our nature and decisions.


The stomach is the hub of our mind. There are nearly 200 million nerve cells in our intestines, which is almost as many as in the brains of dogs and cats. So if they are intelligent, so is our stomach. In a slightly nervous situation, we feel "butterflies" in our stomach, we have a "sensitive" stomach, sometimes we decide "by gut feeling" - all these expressions describe our second brain.Sometimes you get the feeling that the upper brain is not the only captain in the ship.


What do scientists know about our gut-brain interactions? Actually, not enough. Scientists are still discovering how signals are sent between the stomach and the brain, but thanks to advanced technology, scientists are able to better and better study all of this. In addition to nerve cells, our gut also contains hundreds of billions of bacteria that secretly influence our various personality traits.


Michael Gershon, from Columbia University, located in the United States, says that it should be understood that the intestine is a very important organ, not just a snake-like formation. It is a very sensitive and intelligent organ. Today it is clear that there are nearly 200 million nerve cells in the intestinal wall, they are found throughout the digestive tract and they help us digest food. Digestion is a surprisingly complex process. There you have to perform feats that are very difficult to imitate in the laboratory, such as breaking down the food we eat into tiny molecules that can be absorbed by the body and keep our body functioning. However, this requires a lot of nerve power.


Our two brains resemble each other like brothers. The central nervous system is located in the upper brain, the enteric nervous system (ENS) is located in the lower brain. The reason evolution gave us two brains is similar to the reason we keep a personal computer on our desk. By transferring some of the powers to the peripheral gut, the system is more efficient. It can do whatever it wants, the upper brain doesn't have to be enlarged to accommodate millions of extra neurons. Digestion can occur independently, independent of the upper brain. Researcher Michael Neunlist, who works in France and is one of the leading experts on the enteric nervous system, knows that the first in the history of our two brains was far from what we think. According to him, the ENS was our first original brain and it developed in the same digestive tract. The upper brain began to develop in order to feed us better. If the tasks had not been divided, we would still be spending all our energy on digestion. The evolution of the brain began  about 1.5 million years ago when fire was discovered. Cooked food was easier to chew, required less energy, and we got 16 times more energy with less effort. This was used by the upper brain and thus could be developed further. There was energy left over that the upper brain could use to develop.


Cooking food thus allowed us to overcome some physical obstacles, or in other words, we left over the energy that the big brain needed to develop. As the brain developed, we were able to think about things other than digestion. In theory, it would work well for the upper brain to think and the lower one to digest. But the matter is a bit more complicated, because the two nervous systems are closely connected through the vagus nerve and are in constant communication, and they do this with the help of neurotransmitters. Neurotransmission is the language that nerve cells communicate with each other using neurotransmitters, which are like words that each nerve cell uses and understands by other nerve cells. One such word is serotonin. In the upper brain it means well-being, while in the lower brain it sets the pace of our digestion and regulates the immune system. 95% of the body's serotonin is produced in the stomach. Serotonin acts in the digestive tract, but surprisingly it also seeps into the bloodstream, affecting the brain, especially the thalamus (a collection of nerve cells in the brain), which manages our feelings and is involved in emotion regulation and it in a very complex way.


Today, scientists can confirm that the stomach can also affect feelings. Under normal circumstances, we may not know anything about the communication between the brain and the gut, which is why it is also difficult to study. We get a more accurate overview of how things work when something goes wrong.


Irritable bowel syndrome (English abbreviation IBS), which causes abdominal pain, diarrhea and constipation, absorption problems, is a condition that can be used to successfully study stomach-brain communication. It is a common health problem considering that every tenth person suffers from it. Conventional research methods such as colonoscopy, gastroscopy, etc. does not detect abnormalities and everything seems to be in order.


In the case of IBS, researchers believe that it is a communication disorder between the brain and the digestive tract. What causes these communication problems? The researchers are based on the hypothesis that IBS is a communication disorder between the mucosa and nerves. The reason is believed to be in the intestinal walls, more precisely in the nerve cells there. In order to confirm this hypothesis, the intestines of sick and healthy people were studied. Studies have shown that neurons in the intestines of IBS patients are more active than in healthy people. This is the so-called "intestinal neurosis" (neurosis - a health disorder caused by psychological factors).


Irritable bowel syndrome can be caused by emotional factors such as stress or a traumatic event.  The treatment of this has been helped by hypnosis, as we carry emotions with us in our stomachs. In the situation of irritable bowel syndrome, the nerve cells of the gut are very active. Hypnosis calms and balances, and thus disturbing signals that the "second brain" sends to the upper brain can be made more bearable for the patient.


Our body chemistry constantly affects our senses. For example, our dreams depend on serotonin (its release during sleep). The enteric nervous system, located in the gut, can affect how we feel by sending signals to the brain that do not reach consciousness. The ability to think clearly, to have a positive attitude towards life, better resistance to depression and anxiety and other different emotional states are greatly influenced by exactly those signals that reach the brain. In this sense, the stomach is definitely an influencer of the subconscious.


The anatomical similarity between the two brains is so striking that scientists wonder if the stomach and the brain share the same diseases. For example, depression and Parkinson's disease can start in the stomach. Parkinson's disease was long thought to attack a part of the brain called the substantia nigra. But it has now been discovered that it also affects the neurons in the gut, as the disease causes severe indigestion.  The disease begins with severe digestive problems and only in the next phase does the disease affect areas of the brain, causing mental and balance disorders. Researchers took intestinal biopsies from a Parkinson's patient and found that nerve cells in the digestive tract had the same type of nerve damage as in the brain. So the ENS opens like a window to the brain. Someday, a simple intestinal biopsy could be helpful in finding people who belong to the risk group of the disease, because the first signs of Parkinson's disease can already be seen in the intestine 20 years before motor disorders. Therefore, to better treat the senses, it is necessary to examine the stomach.


While Western medicine focuses mainly on treating symptoms, Chinese medicine starts from a holistic point of view, that the human body is a whole and different energy flows pass through our body. In order to heal, the root cause of the disease must be found. Hiinlased on 3000 a kasutanud nõelravi ja  kunagi pole olnud kõht tähtsal kohal, kuniks 1972. aastal dr Zhiyun Bo selle avastas. Ta_cc781905-5cde -3194-bb3b-136bad5cf58d_operates in Canton Hospital, China, which has 7 million patients per year, and the hospital's pharmacy dispenses 10 tons of medicine, both Chinese and traditional medicine, every day. The professor discovered particularly sensitive zones around the navel. The navel plays an important role in the whole body. More than 5,000 students around the world are now practicing abdominal acupuncture according to Professor Bo's teachings.


Scientists admit that they are far from fully understanding the brain-axis. The community of bacteria living in our guts is the densest ecosystem on the planet. There are 100 times more bacteria in our stomach than our own body cells. It is a micro-system within a macro-system. In fact, we are ecosystems, we are more bacteria than people. We are like passengers on a bacteria bus. We all carry up to 2 kg of bacteria with us, they provide us with 30% of the total daily calories, because we cannot digest all the food ourselves, they do it for us. We give them food and shelter. They give us energy and see what is safe for us and what is harmful, that is, they assist our immune system, which is the largest system of the body. Bacteria keep our immune system active.


It is important to know how bacteria colonize us when they play such an important role in our health. In the womb, the baby's intestine is sterile. From the moment of birth, billions of bacteria begin to colonize the newborn. Over time, a microbial community unique to that individual develops. Whether the child is born by caesarean section or naturally,   whether the child is breast-fed or bottle-fed, whether the child received antibiotics after birth - all this affects the community and development of the child's microbes.


In order to find the perfect microbiota recipe, it is necessary to know which bacteria this community consists of. Professor Dusko Ehrlich, a microbiologist studied the genome of microbiota with other scientists. This super study was completed in 2010, examining the genes of millions of bacteria. It was discovered that the microbiome of humans can be divided into three enterotypes. So, in addition to blood groups, we also have different enterotypes. Enterotype does not seem to be related to where a person lives, what gender they are, or how old they are. These different types all produce vitamins and provide energy, but each in their own different way.


The main goal of researchers is to gain an understanding of the role bacteria play in the development of diseases. For example, we can see a predisposition to diabetes, heart and liver disease just by looking at a person's microbiome. Therefore, in addition to the blood sample and urine sample, a simple stool sample should also be added to the usual analyzes in the future.


Studying the microflora of obese people, a certain bacterium from the family Akkermansia rare especially in obese people, normal weight people have enough of it. An experiment was done where mice were fed a high-fat diet, and the mice that had this bacteria took twice as long to become obese. This bacterium lives in the mucus of our intestines, acting on the cells of the intestinal wall, activating genes that direct the body to burn more fats. In terms of obesity, however, scientists believe that the main cause is our behavior, i.e. diet and general lifestyle, 10% is influenced by genetics and 10% by bacteria.


We do not yet know the mechanisms of action, how a particular bacterium affects our body chemistry, well enough. You could say that the third brain is the intelligence of bacteria. They have a genetic repertoire and influence who we are.


Whether probiotic supplements really are as beneficial as they are said to be is still in question, as these studies are usually commissioned by the large supplement industries and the companies that sell them. Life is not easy, not even for bacteria. Probiotics are made from a wide variety of bacterial species. A single bacterium is a factory that produces thousands of molecules. It certainly cannot be said that one molecule - one effect. It is only known that antibiotics kill bad bacteria, probiotics help invigorate and restore good microflora. In fact, very little is known about how exactly probiotics affect our body.


We think that this ecosystem is somewhere far away from us, like in the Amazon rainforest. In fact, it is within us and it affects us greatly. You cannot distinguish yourself separately, you are one biological entity.Scientists' understanding of our body has changed. We are hundreds of billions of bacteria, billions of nerve cells. All of this is still too complicated to fully understand.




The summary was made by Sandra Tamm


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