What is a microbiota?

A microbiota is “a set of living micro-organisms in a given ecosystem (environment).”
The human body is composed of different microbiota, like the microbiota of the skin, lungs, vagina. But the one we will focus on is the gut microbiota.

What is the gut microbiota?

The gut (or intestine) microbiota is localized in our colon (large intestine). It is composed of a thousand of billions of bacteria, viruses, non-pathogenic mushrooms for our body.

The gut microbiota is quantitatively the most important microbiota in our body. All these bacteria would represent about 2kg of our body weight.

What is its role?

Immune system

In recent years, the gut microbiota is at the heart of the research.
It would have a major impact on the functioning of our immune system and especially on the development of auto-immune and inflammatory diseases.

A study has shown that a disturbance of the gut microbiota in young children can cause effects on the immune system and subsequently cause certain diseases as adults.

Other scientific studies have shown that an imbalance in the gut microbiota can increase the risk of food allergy.

Digestive system

The intestine microbiota allows the digestion of certain compounds (eg. polysaccharides) that have not been digested by our body in the previous stages of digestion.

It helps to nourish our intestinal flora, as well as absorbing some nutrients not previously available.

Neurological system

The intestinal microbiota would also have an impact on our “emotions”.
As a matter of fact, it could play a role in our mood, on our cognition (knowledge functions) but also on our mental health.

Some studies have looked at the interactions that our gut microbiota may have with mental illnesses such as autism or depression.
Modulation of the gut microbiota could have an impact on the symptoms of certain mental illnesses.

Numerous results have shown that a quantitative reduction of the gut microbiota and its diversity lead to behavioural changes in adults (cognitive disorder…).

In children with autism, modulation of their gut microbiota through an 8-weeks treatment showed an improvement in their communication and behaviour.


The gut microbiota would also have an impact on the development of obesity.

Indeed, studies have shown that intestinal microbiota differed between obese and non-obese rats. The mucus that forms our gut microbiota is smaller in obese rats, which leads to greater absorption of compounds and therefore a greater ability to extract calories.

When a gut microbiota is transplanted from an obese person to a mouse who is born without intestinal flora, we can observe an important gain of weight. This situation could differ if we transplant gut microbiota that comes from a “thin” person.

How to maintain a healthy gut microbiota?

It is, therefore, necessary to take care of our gut microbiota. And this goes through a healthy and balanced diet.

The intestinal microbiota feeds and diversifies thanks to the food we bring to it. To stay healthy, bring the fuel your body needs by choosing quality products!


  • Gensollen T. And al. (2017). Correlation between early-life regulation of the immune system by microbiota and allergy development. The journal of allergy and clinical immunology.
  • Iweala OI. And al. (2019). The Microbiome and Food Allergy. Annual review of immunology.
  • Appleton J. (2018). The Gut-Brain Axis: Influence of Microbiota on Mood and Mental Health. Integrative Medecine.
  • Abdessamad El Kaoutari and al. (2014). Le microbiote intestinal et la digestion des polysaccharides. Medecine Science.









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