Gut and Brain an alliance, supported or disturbed by microbiom
Milliards of bacteria living in the gut, a sensitive System with enormous influence
How your gut can influence your Brain?
The latest research in neuroscience and biopsychology spot on the interactions between the brain,
the gastrointestinal tract and the bacteria within the gastrointestinal tract. It is in both
directions and called the brain–gut–microbiome axis. Gut bacteria have an influence on
cognition and stress‐related behaviors and the pathogenesis of a number of disorders in
which inflammation is implicated, such as mood disorder, autism-spectrum disorders,
attention deficit hypersensitivity disorder, multiple sclerosis, and obesity, anxiety, and
depression. It is important to know and support the role of the axis in humans and improve
health by prevention and intervention aiming this system. Obviously, we have to understand
that functional gastrointestinal disorders such as irritable bowel syndrome are a disorder of the
axis and not an isolated problem of the gastrointestinal function. The researchers of how
microbes within the body can interact with human brain and behavior show more
interactions of human psychology as an obviously holistic manner. We have to ask ourselves
did the way we changed our environment, our food our habits, change our gut microbes? May
this be one reason for increasing disorders and psychological problems? What could be ways
to support our gut microbiome and prevent negative impact on Brain?
Your Gut your brain and your Behaviour
Let´s spot on microorganisms because the intestines are a place of a rich diversity of bacteria.
These bacteria are important for numerous physiological functions, as digestion and
preservation of intestinal barrier. The gastrointestinal tract has an own nervous system. The
brain communicates to the gut, which influences its sensory and secretory function, and in
return, it receives information from the gut. This communication between the gut microbiome
and the brain uses not only the autonomic nervous system but in addition neuro endocrine
and neuroimmune pathways. Bacteria from the gut can produce neurotransmitters that can
also be found within the central nervous system. There is evidence which suggests that the
diversity of the gut microbiota may be related to brain structure as well. Stress can disturb this
chemical and nervous communication.
Stress is a killer – for your gut microbiota?
In frank, it is not that easy to tell but stress can disrupt the homeostasis of an organism Stress
can change the composition and function of the gut microbiota. Even a mother’s stress during
pregnancy can change the child’s gut microbial. In the same way, dysbiosis can occur due to
chronic stress in early life and into adulthood.
Acute stress has less relevance on the gut bacteria than a chronical exposure. Acute stress has
been found to be associated with potentially adaptive immune responses (suppression of
immunity mounted against intracellular pathogens, but a preservation of immunity mounted
against extracellular pathogens), whereas chronic stress has been associated with a
suppression of both. There is a lack of studies in humans because examiners only way to test
is the stool. But animal models show clearly that stress impacts upon the
brain–gut–microbiome axis. Gut microbiota is altered in patients with major depression, as
well as irritable bowel syndrome. The role of the vagus nerve is particularly interesting here, as
evidence suggests that gut‐brain signaling may be mediated by the vagus nerve.
How Bacteria influence Cognition?
In animal models, the gut microbiota has been shown to interact with host cognition in
numerous ways. In mice, researchers switched off the microbeam of the intestinal flora, with an
antibiotic cocktail. This mouse showed more anxiety. Compared to untreated animals, they
observed much less newly formed nerve cells in the hippocampal region of the brain. The
same mice showed impaired short‐term recognition and working memory because this
formation of new brain cells – called "neurogenesis " – is important for certain memory
functions.Further more the researchers observed altered social behaviour. After re-colonisation
the social behaviour is restored but not social cognition. An another study could reveal that
maternal high‐fat diet had a negative impact on mice offsprings social behaviour that was
reversed by treatment with Lactobacillus Reuters. In rodent models, a specific strain of
Bifidobacterium longum was found to alter cognition as well as stress‐related behaviour and
physiology. Researchers assume the changes may occur due to neurological changes such as
increased myelination in the prefrontal cortex in germ‐free mice, a change which could be
reversed by the restoration of the microbiota. Of course, these results have to be handled with
reason and care until clear human studies are provided. Nevertheless they show obvious connections
between gut – bacteria, brain function and behaviour.
Developing to a healthy person needs a healthy gut in early childhood
Researchers assume sensitive periods for the development of the gut microbiota. The
microbiota of vaginally‐delivered infants differs from those delivered by cesarean. The initial
exposure to the vaginal microbiome on birth leads to a different population of microbes
colonising the gut compared to cesarean delivery. Human psychological and microbial
development are impacted by perinatal factors. Other factors shortly after birth could also
affect the microbiota, such as the use of antibiotics, and feeding pattern, which can result in
impact upon neurobiological development.
Can gut microbes be involved in Autism?
In result of researchers, the evidence is given that the gut bacteria influence social behaviour.
Altered social behaviour in germ‐free animals is complemented by indicators that children
with autistic spectrum disorder (ASD) have a differing gut microbial profile. Researchers
assume that immune pathway within the brain–gut–microbiome axis may be a plausible may
be the cause of the social behaviour. Inflammation in the gut may have social behaviour as a
result but same time, a social threat may lead to a proinflammatory immune response.
Globalisation, modern Lifestyle and the change of the guts
As we saw, social environment can have multiple influences on the gut microbiome. One may be
the change in diet due to Globalisation. A modern diet, high in carbohydrates and processed
foods influences the gut microbiota. Studies found differing and often more diverse
microbiota in populations with diets that are differing from this modern style. Studies
compared here with people of different origins, where the diet is similar to when agriculture
and animal husbandry were introduced c. 10,000 years ago. Concluding, that our diet made by
culture may become our fate for health, cognition and behaviour via the brain–gut–microbiome
The modern way of growing and farming is generally designed to reduce microbial diversity.
The herbicide Glyphosate is used world wide. In Europe, it was in a discussion but it was not
banned. It was found a strong coherence with Glyphosate, the gut microbe and the
detoxification of Xenobiotics. Via the gut, macrobiotic Glyphosate inhibits Cytochrome P450
(Cyp450) as a result, many toxins accumulate in a higher dose in the body and cause several
May your diet change your Psychology
Research, as mentioned above shows clearly: yes. A vegan diet reduces in the potentially
pathological microbiota, a high‐fat diet increase risk of inflammation. If you like to control
your gut microbe, just learn to control your diet. Research of polyunsaturated fatty acids
showed in laboratory animal models to alter microbial composition as well as improving
cognition and to enhance adherence of probiotic bacteria to the gastrointestinal tract Research
in humans discovered that docosahexaenoic acid, eicosapentaenoic acid, and total omega‐3
polyunsaturated fatty acids in people with major depression are low and omega‐3 fatty acids
may have a positive effect on depression. These are only very few samples how diet impacts
the microbial and by this way healthy and happy.
Pro- und Prebiotika
Probiotics are living bacteria, that when ingested in sufficient quantities, help to change and
improve the gut microbes. For example, probiotics are able to reduce cortisol output in
response to an acute stressor. Even probiotic fermented milk drink can change brain activity.
Another study indicated that fermented milk of a Lactobacillus Helveticus provides improved
sustained attention and a well as a recent study shows changes in frontal EEG and better
learning memory performance. There are several hints why these effects can be induced,
including immune system effects, vagus nerve activation, tryptophan metabolism, and
microbial metabolites. Probiotic bacteria can promote the production of neuroactive
substances such as serotonin and GABA.Research clearly shows that probiotics can influence
anxiety and depressive symptoms. Probiotics as Lactobacillus Plantarum showed an effect on
irritable bowel syndrome, the pain was reduced. Hint: In researchers, the effect of Probiotics is
tested mainly with only a few types of bacteria. At present, there is no upper limit for levels of
histamine and tyramine in fermented products available, which may cause issues, especially
in individuals with sensitivities and/or defect enzymes like DAO and HNMT. For this case
Supplements may be recommended because they are composed well. Pay attention to take
supplements that have sufficient quantities of bacteria.
Prebiotics are food ingredients that improve health by modulating the colonic microbiota.
Fiber is, in general, an important part of a microbial supporting diet, because it is the main source
of microbiota-accessible carbohydrate in the diet of humans. There is different special fibre
available to support digestion, like Psyllium Husk. A well-researched prebiotic is inulin (not
insulin!) a nondigestible oligosaccharide. A study showed it is stimulating Bifidobacterium
adolescents and Faecalibacterium prausnitzii.
The role of gut microbes, probiotics, and vitamins
Vitamin B12 (cobalamin) is one Vitamine of the Vitamin B group, which is
known to support the nervous system and brain function. Vitamin B12 and other B-
vitamins can be produced by typical probiotics like Bifidobacterium, Lactobacillus.
The most famous B12 producer is Lactobacillus Reuters is naturally found in human
intestines. This may be beneficial in fermented food and in the human gut. At least two
groups of organisms in the small bowel, Pseudomonas and Klebsiella sp., may
synthesise significant amounts of the vitamin, too, as well, as Escherichia coli.
Vitamin B9 is a very important Vitamin for Methylation. Lactobacillus Plantarum
are expected to produce folate L. Plantarum is found in fermented food. Other
Probiotics which are likely to produce Folate:
– Bifidobacterium animals (used in Danone & Bifidus yogurts like Activia)
– Bifidobacterium locum (used probiotics)
– Lactobacillus acidophilus (most common probiotics)
– Lactococcus lactic (used to make buttermilk and many kinds of cheese including Brie,
Camembert, Cheddar, Colby, Gruyère, Parmesan, and Roquefort)
– Leuconostoc lactic (used to make kefir and sauerkraut)
– Streptococcus thermophilous (used to make yogurt)
Vitamin B2 Lactobacillus fermented, which is found in sourdough and in many
probiotics. It is also noted for its ability to reduce cholesterol levels and to act as an
antimicrobial and antioxidative. Research is not far on this matter, but it is sure,
that probiotics and gut microbiota can produce some of the Vitamins which are
very important for the nerve system.
Research data demonstrate that vitamin D regulates the gut microbiome and that
deficiency results in dysbiosis, leading to greater susceptibility to injury in the gut.
Just some thoughts by the author:
Some people are critical against this holistic way of disorders and disease. But just mind the claimings here are based on scientifical research, not traditions or experience. Gut may not be the cure of all disease and it is not the core. But it is involved in many symptoms and syndroms and can turn things to a better or a worse, so it is worth minding it. Gut is not only involved in the brain axis. There is many other organ and health systems and comminicating connections. Gut plays infact a main role in a network involved in health and benefit or weakness and disease.
You may also like: