Is there really a connection between the gut and the brain?

At a first glance, it may seem that human brain and gut are two separate organs that have different functions. It is clear that brain is the organ that controls processes in the gut.

But did you know that this connection works also other way around?

Gut and Intestines have impact on the brain function to a large extent. Just like mental problems can cause gut issues, bowel activity problems can cause anxiety and other mental problems.

Gut-brain Axis

Connection between Gut and the Brain is really tight. For example, you can just think about the food and gut already reacts to the food thought and start its processes before the food even arrives there. explains why we always have stomach upset under the influence of stress. Stress can worsen existing health problems and maximize pain feeling. That is why doctors always focus not only on drug treatment, but focusing on mental statze of pacients.

Communication between the gut and the brain is based on neurotransmitters. Neurotransmitters are produced by the brain and their main purpose is emotion control and even control of body functions. Very important neurotransmitter is Serotonin. It is responsible for the feeling of hapiness and satisfaction. It is interesting that serotonin is not produced only in the brain, but also in the guts. 95 percent of Serotonin is produced there. Bacteria in the Guts are also producing GABA, that reduces feelings of anxiety and fear. There is a new trend of treating anxiety, bipolar depression and depression patients with specific probiotics.

Vagus nerve

Because the physic and biochemical connection between the brain and the gut is very important, scientists came up with the name Gut-Brain Axis. Guts contain 500 millions of neurons, that are sending informations to the Brain, or they are receiving them. Most important nerve connection is Nervus Vagus (Vagus Nerve). Studies have shown that people with Crohn disease have dysfunctional Vagus nerve. People that suffer from loss of connection between the Brain and the gut, cannot relieve symptoms with basic probiotics. In a normal circumstances, consuming probiotics with lactobacillus cause reduction of stress hormones release into the bloodstream.

Probiotics vs. Prebiotics

There is more and more evidence that gut microbiome has radical impact on central nervous system. In the human body, there are millions of bacteria and most of them live in the guts. As we mentioned, using probiotics can keep the good microbiome. World health organisation define  prľobiotics as a live species, most often bacterias and yeast fungus, that can improve humans health when consuming in heathy amounts. You can get a dosage of probiotics either by a supplement or by consuming fermented foods such as yoghurts, kefir, and sauerkraut. Most famous probiotics are Lactobacillus and Bifidobacteria. Each group of these bacterias can be beneficial for different health problems. Therefore it is important to choose the right probiotics for yourself.

    SO what is the difference between probiotics and prebiotics? Both are beneficial for the body, but the difference is that while probiotics contain real live bacteria, prebiotics are carbohydrates, or fiber that serves as a nutrition for probiotics to survive in the gut. Studies have shown that supporting digestion with prebiotics helps to fight diabetes, support healthy immune system, impacts insulin excretion , and has an impact on blood cholesterol levels. Prebiotics also reduce the risk of infections of digestive tract and support balanced mood in people. There are experimental studies that have even shown some promise in fighting cancer.

Lactobacillus Rhamnosus

One of the most important bacteria living in the human colon and gut is Lactobacillus Rhamnosus.  Manufacturers often add Lactobacillus Rhamnosus in the dairy products, but you can also buy it in a supplement form. Lactobacillus produces an enzyme lactase, that breaks down milk sucrose. Benefit of Lactobacillus Rhamnosus is that bacteria can adapt to the human body and stick to the intestinal wall. That is why supplement with Lactobacillus Rhamnosus can work long-term in the human body.

Similar to other probiotic bacterias, L.Rhamnosus supports immune system, inhibit pathogens and help with homeostasis. L.Rhamnosus is a bacteria that is beneficial in a fight against inflammatory diseases that have large impact on a person´s life, such as Irritable bowel syndrome. These diseases often go hand in hand with depression or anxiety. The important feature of L.Rhamnosus is that it increases production of short-chain fatty acids such as butyrate.


It is extremely import to take care of gut microbiome. Healthy gut microbiome supports metabolism of vitamins , for example vitamin K and some of B vitamins. It also converts fiber to short –chain fatty acids , such as butyrate, propionate and acetate. These are essential for the body to start its metabolic processes. Butyrate and other short-chain fatty acids are strenghtening intestinal walls and ensure that substances that may be harmful to body will not get inside. Many studies have also shown that butyrate prevents colon cancer. Butyrate helps hypercholesterolemia and genetic metabolic diseases and it also supports neurogenesis – creation of new neurons.

Intestines and neurodegenerative diseases

Dysbiosis – impaired microbiome in the gut and intestines – can lead to digestive problems and even to formation of neurodegenerative diseases, such as multiple sclerosis, Alzheimers and Parkinson disease. Disbiosis can cause  increased intestinal permeability within the gut-brain axis – that means a variety of microbes can get to the body from the gastrointestinal tract. That can cause demyelination of the neurons, which is the main cause of neurodegenerative disease mentioned above. Using right probiotics can be good prevention against neurodegenerative diseases.

Ghrelin – Hunger hormone

Gut microbiome can even have an impact on a person´s bodyweight. People often rely on diets when they are trying to get lean, but many  times the results are short – term and kilograms are gained back fast. Hormones can be responsible for this  , as they regulate appetite, and have an impact on fat storages. Ghrelin has a large impact on gaining weight, because it is a hunger hormone. Ghrelin sends signals to the brain that it is time to eat.

Ghrelin makes it harder to stick to any form of diet. It is created when we are hungry and because of Ghrelin we feel hungry.  More Ghrelin we have in our body, more hungry we are. But Ghrelin is not only bad and his purpose is to keep reasonable amount of fat in our bodies. Ghrelin does not only impact feeling of hunger, but it changes the way we perceive taste, it impacts sleep cycle as well and it has an impact on reward system in the brain as well.

Fermented foods

So how to effectively fight obesity, dysbiosis of the intestines and their consequences? One of the options is to use supplements with the right amount of probiotics and consuming fermented foods that contain probiotics as well. Yoghurts are rich in bifidobacteria. It is important to choose the right ones, because not all of the yoghurts contain bifidobacteria. Sometimes, bifidobacterias are killed in the process of making these products. Another good option is to consume Kefir. Kefir improves digestion and it also has anticarcinogenic properties and it supports imunity.

You should also try Kombucha, which is fermented green or black tea. Sauerkraut also has probiotic properties, and it contains a lot of vitamins and antioxidants. It is important that Sauerkraut is non-pasteurized, otherwise it will not have probiotic properties. Great source of probiotics are also pickles. These are great source of vitamin K. Cheese is also beneficial for the gut microbiome, especially mozarella and cheddar.


How to take care of your gut microbiome?  Proper nutrition with the focus on probiotics and prebiotics is the most important thing. It is also important to eat slowly. Focus on what you eat and how it impacts your body, use all of your senses when eating food. You should focus not only on eating, but the food quality we buy and also on proper eating habits. Avoid impulsive buying and buy the food you really need and will benefit from. Processed foods and foods with added sugar will not help our gut microbiome. It is important to consume plant-based foods with high amounts of fiber.

Consuming foods high in collagen, such as bone broth and salmon, is very beneficial for gut microbiome. Vitamin C and Glycine support collagen production in the body. At the other hand, collagen production is limited by excessive sugar consumption, rafinated carbohydrates and smoking. We should also eat when we feel normal hunger, not in the moments when we are extremely hungry because it increases the risk of eating high-sugar and high-fat foods.

Stress reduction is very important when restoring healthy gut. Stress and digestion is closely related. The lower the stress, the better microbiome we have and vice versa. Also, have enough sleep. Quantity and quality of sleep have impact on gut microbiome. And don´t forget to drink enough water.






DISCLAIMER: The information included in this article is intended for entertainment and informational purposes only. It is not intended nor implied to be a substitute for professional medical advice. Prior to buying anything, check that it is compliant where you live with your current government laws.