Intestinal microbiota: The second brain!

by Nathalie Hutter-Lardeau and Océane Berthé, dietitians-nutritionists

What is the intestinal microbiota?
The intestinal microbiota refers to the collection of non-pathogenic bacteria, parasites and fungi found in our digestive tract. It is the largest microbiota in our body as it represents roughly 2 kilos of micro-organisms.
These micro-organisms are particularly abundant in the colon. Just over 1000 bacterial species make up the composition of the human microbiota. Each of us has around 200 of such microbiotas in our body.
Each person has his or her own unique microbiota, specific in its combination of species and formed at birth. Although each person’s microbiota is unique to them, all microbiotas fulfil roughly the same function. Our microbiota performs the following role in metabolism and digestion:
The gut microbiota enables the process of fermentation of certain food residues which have not been digested as they leave the small intestine
It contributes to the assimilation of nutrients
It regulates the storage of fats since it works with metabolic processes in several organs (liver, adipose tissue, etc.)
It also participates in the synthesis of certain vitamins such as vitamin K or vitamin B8 and B12.
Its role in the immune system:
It is important for the maturation of the gut immune system thus contributing to preventing allergies
It forms a protective barrier in the intestinal wall to prevent pathogenic species colonizing the digestive tract.
Although the microbiota is relatively stable over time, its composition throughout a person’s life can vary according to external conditions: diet, viral or bacterial infections, certain medicines (especially antibiotics), physical activity, lifestyle (smoking, stress…).
When the gut microbiota is subject to an imbalance, it tends to return to its initial state within 1 or 2 months. However, a series of imbalances may, over the long term, have negative impacts on your health.