Gut-brain axis: Why we have butterflies in our stomachs

Veröffentlicht am: August 01, 2024
Dr. med. Wolfgang Bachmann
Dr. med. Wolfgang Bachmann

General practitioner

Have you ever had "butterflies in your stomach"? Or have you listened to your "gut feeling" to make a decision? 

The sensation emanating from your gut indicates that your brain and gut are connected. This communication network between the two different organs in your body is known as the gut-brain axis. 

➤ Find out more about the extremely interesting connection between your brain and your gut and the various effects and studies on this in this guide.

Contents

What is the enteric nervous system (ENS)? 

The intestine is the home of the enteric nervous system (ENS) - the so-called abdominal brain.

Interestingly, the enteric nervous system has more nerve cells than our spinal cord.

The ENS consists of two thin layers with more than 100 million nerve cells that line the entire gastrointestinal tract and control blood flow and secretion formation .

Unlike the brain in your skull, the enteric nervous system can't pay your bills or fill out your tax return. Instead, it controls all aspects of our digestion from the swallowing process, to the release of enzymes, to the blood flow that determines nutrient absorption and excretion. 

For a long time, researchers were not sure whether the ENS was only responsible for our digestion. Instead, they now believe that its complexity means that it is connected to our brain and communicates with it in many different ways. This is why we sometimes have the feeling that we are "thinking" with our stomach, for example when we have a "sinking feeling in our stomach" because of a decision to be made or when the familiar butterflies are flying around in our stomach. 

How do the brain and gut communicate?

Our brain and gut are physically and biochemically connected. 

One of the two connections is formed by the vagus nerve, one of the largest nerves that connects your gut to your central nervous system in the brain (CNS). It can send signals in both directions, i.e. from the gut to the brain and vice versa. 

  • A very interesting human study carried out in 2014 confirmed that the vagus nerve sends only very weak signals between the two organs, especially in people with irritable bowel syndrome or Crohn's disease. 

  • Another study showed this link even more strongly, particularly in relation to stress. Researchers found that mice given probiotics through their food had a reduced amount of stress hormones in their blood. When the vagus nerve was cut in two, the probiotic had no effect. 

These effects suggest that the gut-brain axis plays an important role , especially during stress. 

Another way in which the central nervous system and the enteric nervous system can communicate with each other is through neurotransmitters. 

These are chemical substances that are produced in the brain and control our feelings and emotions.

Interestingly, many neurotransmitters are also produced by the cells in the gut and the microbiome present there. One of the most important neurotransmitters, for example, is gamma-aminobutyric acid (GABA). GABA has a calming effect, especially in cases of stress and anxiety.

Gut-brain axis as a link between depression and bowel disease?

For years, it was believed that people suffering from anxiety or depression could have irritable bowel syndrome and/or functional bowel problems. However, recent studies have shown that the reverse can also be the case. 

Studies show that 80 % of the signals of the gut-brain axis are sent from our gut to our brain and only 20 % from our brain to our gut. 

This means that irritations in the gastrointestinal system send signals to the central nervous system, which can trigger mood swings. This finding is very important!

➤ Did you know that30-40% of the population will develop functional bowel problems in the course of their lives? 

The new understanding between the connection of the ENS and CNS helps to explain the effectiveness of treatments for IBS and bowel disorders with antidepressants or cognitive behavioral therapies. It means that therapies that help our brain can, to some extent, also promise improvement to our gut brain .

This is why certain antidepressants are also prescribed for irritable bowel syndrome, for example. This is not because the problem is caused entirely in the patient's head, but because the medication can have a partially positive effect on the nerve cells in the intestine. 

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Gut-brain axis: How do we benefit from the new findings? 

Thanks to the knowledge of the very pronounced connection between the brain and the abdominal brain, depression can be treated through the stomach and vice versa, the treatment of stomach problems can be treated in the head. 

We have put together some tips and recommendations for the health of your brain and intestines:

Take probiotic capsules

It is highly recommended to take probiotics capsules or powder. As research has shown, the health of your gut contributes enormously to the health of your psyche. We therefore recommend that you nourish and strengthen your healthy gut bacteria. 

Choose your food wisely: 

You should also eat foods that have a positive effect on your intestinal bacteria. These include 

  • Omega-3 fatty acids
  • Fermented foods (yogurt, kefir, sauerkraut)
  • Fiber-rich foods (nuts, seeds, fruits and vegetables),
  • Foods rich in polyphenols (cocoa, green tea, olive oil) 

Take 5-HTP to increase your serotonin levels 

5-HTP is a precursor of serotonin, which can have a brightening effect on our psyche. The capsules can be taken orally, whereby the active ingredient reaches the brain directly and can easily pass through the blood-brain barrier. As a result, up to 90 % of it is converted into serotonin and absorbed by the proteins. 

Use GABA in case of stress 

9 out of 10 people feel stressed at work. So it's good to know that you can also control your stress level via your gut. Gamma-aminobutyric acid is particularly effective when the hyperneurons in your brain are overly active, as is the case with stress. 

Conclusion: 

The gut-brain axis is the communication system between the gut and the brain and is connected by neurotransmitters and neural pathways. Research has shown the incredible bidirectional impact gut health can have on our psyche, bringing the health aspect of both "brains" to the forefront .

 

Sources: 

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