Sind dein Mikrobiom und dein Gehirn durstig? - myBioma

Are your microbiome and brain thirsty?

... how lack of fluids affects our gut and our microbiome, and changes the shape and activity of the brain.

Even a slight lack of water of 700ml triggers the body's alert system. Since we consist largely of water, this can have serious consequences. Without this water, many biological processes would not function properly. We would not be able to see, hear, smell, feel, taste, think or move. In a nutshell: Our cells would not be able to survive without this fluid.

Water balance of the body

Without water we would not be able to survive, as it is essential for many important processes in our body. (4)

Lack of water in the body can be evident in many ways. These include tiredness and exhaustion, elevated cholesterol levels and high blood pressure, kidney and bladder problems, weight gain, joint pain and digestive problems.

This can lead to constipation or a lack of important minerals, which can have a serious impact on our microbiome.

Lack of fluid in the intestine also leads to an increased risk of inflammation, as good “moistening” of the intestinal mucosa is essential to maintain its protective barrier. This can go so far that it influences the composition of the intestinal flora and its interaction with the immune system.

Brain MRT

The fMRI image (functional magnetic resonance imaging) of a test subject's brain shows expanded brain chambers (ventricles) and condensed switching nuclei (e.g. thalamus). (5)

Researchers have also shown that dehydration (lack of fluids) can significantly affect the brain. Its form and its function in terms of task fulfillment are significantly affected.

When there is a lack of fluid, parts of the brain can swell (!), disrupting neural signals and making it more difficult to complete certain tasks.

An experiment showed that test subjects who suffered from a lack of fluids after exercising were more likely to fail repeat tasks and that their brains showed noticeable changes.

Combined with heat and exertion, lack of water poses an even greater challenge to our bodies.

The aim of the researchers is, for example, to find out how the knowledge gained can ensure increased occupational safety during strenuous work in hot environments and help prevent accidents. This question also plays an important role in competitive sports.

In order to explain the processes in the brain in more detail, it is important to mention that certain structures, the brain chambers (ventricles), expand when dehydrated (!). However, when the test subjects consumed water during training, these fluid-filled spaces in the middle of the brain shrank again.

Neural circuits were also affected by the lack of fluids.

It should also be noted here that overhydration is also not effective and can have harmful health consequences.

Woman with picture of drawn intestines.

It is important to drink enough to prevent constipation, for example. (6)

In summary, make sure that you drink enough, especially during the hot summer days, to keep your microbiome, your digestion, your brain and in general your whole body functioning and remaining productive.

Do you already know what the diversity and balance of your microbiome is, which can be altered by a lack of fluids? Try it here and we'll help you find out.


This article is intended for informational purposes only and should not be construed as medical information or instructions. The recipes are intended for inspiration and are not intended as therapeutic measures. If you have any health problems, we recommend that you contact a doctor or other expert immediately


  • Georgia Institute of Technology”Dehydration Alters Human Brain Shape, Activity and Slackens Task Performance.” (accessed August 21, 2018).
  • Useros, Noemi Redondo et al. “HYDRAGUT study: Influence of HYDRAtion status on the GUT microbiota and their impact on the immune system.” (2015).
Medical Doctor and Microbiome Expert
Ina is a medical doctor and is passionate about analysing the gut microbiome and its importance for health!