The Bacteria in Your Gut Controls Your Mind

gut flora probiotic

This Is How Your Gut Controls Your Mind.

Have you ever had that feeling? A feeling that suddenly makes you anxious or gives you the impression that something is wrong? It’s not just a rhetorical figure, because there’s actually science behind it.

This is due to the microbes in your intestine that communicate with your cognitive system through a vagus nerve, and vice versa. Let’s see what happens in the intestines when it starts sending signals to the brain that cause certain problems like anxiety or depression.

Are We Guided By Instinctive Feelings?

A neuroscience scientist at Florida State University concludes that you are, if not by choice, perhaps subconsciously. Studies by psychology professor Linda Rinaman suggest that the signals between the brain and intestine exert a strong influence on our emotions, mood and decisions ; usually by inducing you to avoid certain situations.

The article, published in Physiology and co-authored by James Maniscalco, postdoctoral fellow at the University of Illinois at Chicago, allows researchers to better understand the functioning of the intestinal-brain circuit.

” We are excited about the research on the Animals examined here, including our own work, because it can translate into humans, ” said Dr. Rinaman. “We know that the intestinal-brain pathways are very similar from one mammalian species to another; from mouse to human. We expect that these lines of research will help us better understand how gastrointestinal functions contribute to both normal mental functions and mental disorders.”

So, there might be a link between intestinal bacteria and brain activity in healthy people

Rinaman said the bowel and brain communicate all the time through the vagus nerve. It is a two-way tentacular network linking the cognitive system with the gastrointestinal tract, which has a very large surface area and many “sensors”. The gastrointestinal tract is more than a hundred times larger than the surface of the skin, and it sends more signals to the brain than any other body system.

The vagus nerve is known as the” wandering nerve ” because it wanders through the chest and abdomen, monitoring and controlling digestion, heart rate, blood pressure, immune function and hormone levels. It is the longest of a dozen cranial nerves and functions as a bidirectional circuit that sends messages from the top down from the brain to the body, as well as messages from the bottom up, commonly described as intestinal feelings.

These messages from the intestine to the brain have a powerful influence on our emotions and behaviour, especially in response to disturbing or threatening stimuli and events. The nerve is part of an elaborate system of protection that helps us make decisions, usually by encouraging us to slow down and assess a situation, or to avoid it altogether.

” The vagal feedback signals are very protective and encourage caution, ” said Mr. Rinaman.

Scientific and anecdotal evidence suggests that inadequate diets can cause these protective and precautionary signals to dissipate, resulting in mood and behaviour changes. For example, says Rinaman, a high-fat diet can promote an inflammatory response in the gastrointestinal tract, altering vagal cues and can exacerbate symptoms of anxiety, depression or other disturbed mental states.

Rinaman explains that the types of bacteria in your gut are determined by your diet, and that these bacteria can affect your emotional and cognitive state. What we eat affects the composition of our microbes, changing the products our gut produces. A high-fat diet, in particular, can backfire on the bad bacteria that love these types of foods. People who like fast food produce inflammatory compounds, which opens the door to chronic diseases.

So, we can say that chronic diseases start in your gut!

“The evidence shows that dietary modification, perhaps by consuming probiotics, can have an impact on your mood and behavioural status. This is very clear in animal and Human Studies,” said Mr. Rinaman. “But how does it work? Is this the microbiome you feed in your gut and how these bacteria send signals to the brain through the vagus nerve? This area of research has exploded in recent years and at present there are many more questions than answers.”

Furthermore, it is not yet clear why treatment with electrical stimulation of the vagus nerve helps to relieve clinical depression. Approved for patients who do not respond well to prescription medications or other therapies, stimulation of the vagal nerves modifies the signals received by the brain and can have a positive impact.

Researchers do not understand how or why it works, but its effectiveness generates more motivation for scientists like Rinaman.

” The neuroscience of gut feelings has come a long way in my life, “said Rinaman, ” and we are learning more and more valuable lessons every day.”

How do intestinal bacteria control our mind, our mood, our desires ?


If you want to significantly improve your diet, Rachida reveals the little secrets of a healthy diet in its article the 3V : 3 golden rules for healthy eating

A History Of Bacteria

Many of us still think that bacteria are terrible enemies that need to be eradicated on a massive dose of antibiotic or aseptic spray !

There are indeed bacteria that make us sick, but do you know that the majority of bacteria don’t really want to harm us, but quite the contrary?

We are indeed colonized by billions of bacteria. Don’t panic! The vast majority are for our own good and essential to our health. All these “good bacteria” are found, not only in our skin, but also in our bodies. Among other things, it is our intestine that hosts the most, the famous intestinal microbiota.

But What Are All These Bacteria?

These billions of bacteria are specific to each individual. They help us digest well, produce vitamins, boost our immune system. Good bacteria prevent bad ones from developing. They also control our weight. It is known, for example, that obesity is accompanied by a modified and not very diverse intestinal flora compared to non-obese people, who have a richer flora.

Today, science is formal, even playing a role in our mental health. This all the more justifies why our belly is also called “second brain”.

There is a kind of communication between our intestinal bacteria and our brain and it is known as ” gut brain axis “.

Bad Mood? Anxiety? Shyness? What If It Came From Our Intestinal Microbiota?

It’s hard to believe that by altering the bacteria in our intestines, we could better manage stress, improve our mood and even treat our anxiety or depression. Scientists are formal, there’s a real connection between our intestines and our brains. Improving our intestinal bacteria can therefore positively affect our mood and, in general, our brain function.

Canadian researchers have even shown that “timid” mice, which received a transplant of intestinal bacteria from less timid mice, became more active and curious. This work suggests that our shyness may also be hiding in our intestinal bacteria. It has even been shown in humans that depression may be accompanied by perturbation of the intestinal microbiota.

Other studies show that mice that have no intestinal microbiota at all are very sensitive to stress with high levels of stress hormone.

How Do Bacteria Influence Us?

You could imagine, all those little bacteria whispering in our ears and telling us how to behave. It’s like a science fiction movie. Are we being manipulated by our own bacteria ?

I guess so. Our intestinal bacteria are actually very intelligent. For their own survival, within our body, they are able to influence our brain by producing molecules that can change our behaviours. To feed themselves, they can encourage us to have certain eating behaviours. This could make us feel certain that they are responsible for cravings or, on the contrary, make us reject food that is harmful to them !

Our brain in turn also influences its bacteria. So there are real exchanges between our brains and our intestinal bacteria.

Intestinal Bacteria Regulate Serotonin, the Mood Regulating Hormone

Serotonin is a chemical, or neurotransmitter, that regulates our mood. It is part of these famous hormones of happiness, just like dopamine, oxytocin or endorphins. She is also involved in the management of our emotions, stress but also our eating behaviour and our sleep-wake cycle. Several chemical antidepressants work on serotonin.

It is produced by our brain but mainly in our intestines, and our intestinal bacteria influence its production.

Mice without intestinal bacteria, which are hypersensitive to stress, indeed have lower serotonin levels of 60% compared to mice with normal intestinal microbiota. And when the researchers reintegrated bacteria, they found an increase in serotonin levels.

This shows that bacteria do act on serotonin production and that they can therefore influence our mood.

Intestinal Bacteria: Watch Out For This Delicate Balance!

Our intestinal microbiota is very fragile and nowadays, with our rhythms of life, it is under severe strain. Many factors can alter or unbalance it, such as poor nutrition (additives), antibiotics, Alcohol, Tobacco, lack of sleep, excessive use of cosmetics, pollution,…

5 Golden Rules For Rebalancing Our Intestinal Microbiota For Better Health And Performance

1. Reducing Alcohol And Tobacco

Generally speaking, alcohol and tobacco are the enemies of our health. Alcohol is of course to be consumed in moderation and it is best not to smoke.

2. Avoid Antibiotics

In addition to medication, they may be present in certain foods, such as intensively farmed animals.

3. Prefer Fresh And Unprocessed Or Unprocessed Products

Ultra-processed products contain many additives, such as preservatives, dyes, flavour enhancers. They are also generally too sweet, too salty, too fat and are very poor in terms of nutrition. They are responsible for the appearance of many chronic diseases, such as Type 2 diabetes or cardiovascular diseases (discover 8 good reasons to reduce ultra-processed products).

We must therefore give priority to vegetables and fruit, organic preferences to avoid pesticides. And of course, cooking as much as possible yourself.

It is important to eat good fatty acids, such as omega-3s, which are sorely lacking in our Western diets.

4. Consume Fermented Foods With “Psychobiotics”

They contain probiotics, which are good bacteria allied to our health. Probiotics need prebiotics to implant properly in our digestive system. Prebiotics are fibres found in many fruits and vegetables, such as legumes (lentils, red beans, chickpeas, green peas), oilseeds (almonds, nuts, pistachios) and some roots (dandelion, chicory, Jerusalem artichoke).

A study published in the journal Nutrition in 2015 showed an improvement in depression in patients who took probiotics such as Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium bifidum for 8 weeks. Another probiotic, Lactobacillus plantarum, found in olives for example, increases the production of happiness hormones such as dopamine and serotonin in mice.

The effects of these probiotics on mood, anxiety and depression have earned them the name of psychobiotics.

5. Combat Chronic Stress

Chronic stress, which lasts over time, has many negative impacts on our health, including unbalancing our intestinal bacteria. It is therefore essential to combat this scourge.

Here Are Several Simple Methods To Relax:

Better breathing. Pay attention to her breathing so that she can be in the present moment. 5 minutes of cardiac coherence per day, 3 times per day, or at the slightest stroke of stress have many benefits and really allow to relax.

  • Relax, through the practice of relaxation, yoga, meditation, rigology…
  • Singing helps to relax (not for the one next door, if you’re not singing right !)
  • Do Sports

So, there you go. You should now be aware of some key steps and methods that may seem surprising, but are essential in order to boost your motivation, performance, well-being and overall health.

Human beings are complex. It is to be considered in its entirety, in a holistic way, with those billions of bacteria that act for us at every moment. We respect this beautiful symbiosis.


Akkasheh G, Kashani-Poor Z, Tajabadi-Ebrahimi M, Jafari P, Akbari H, Taghizadeh M, Memarzadeh M., Asemi Z, Esmaillzadeh A. Clinical and metabolic response to the administration of probiotics in patients with major depressive disorder: A randomized, double-blind, placebo-controlled trial. Nutrition. 2016 Mar; 32(3):315-20.

Foster JA, McVey Neufeld KA. Gut-brain axis: how the microbiome influences anxiety and depression. Neurosci Trends. 2013 may;36(5):305-12.

Kaliannan K, Wang B, Li XY, Bhan AK, Kang JX. Omega-3 fatty acids prevent intestinal dysbiosis caused by exposure to antibiotics and late obesity. Int J Obes (Lond). 2016 Jun; 40 (6):1039-42. U.S.A.

Liu WH, Chuang HL, Huang YT, Wu CC, Chou WG, Wang S, Tsai YC. Behavior modification and monoamine inhibitors levels attributable to Lactobacillus plantarum PS128 in axenic mice. Behav Brain Res. 2016 Feb 1; 298 (Pt B):202-9.

Post a Comment

Your email address will not be published. Required fields are marked *