Library · Biological system
The gut microbiota
Make it clearer
A population of microorganisms, which are tiny living things, lives in the digestive tract. That whole group is called the gut microbiota, and many people know it as gut flora.
They are not just passing through. They help keep the mucosa, the layer that lines the inside of the gut, intact so it can go on working as a wall. They supply nutrients the body puts to use, vitamins among them. And they protect against pathogens, the microbes that can make you sick: the gut is not an empty lot, it is a neighborhood that is already lived in.
They are not spread out evenly. In the small intestine the environment is acidic, there is oxygen, there are antimicrobials, which are substances that kill microbes, and everything moves through fast. In the colon, by contrast, conditions support a dense and varied community, made up mostly of anaerobes, bacteria that live where there is almost no oxygen.
What you eat shapes it, and in adult life, although it is fairly stable, it does shift. That said, when that composition gets disordered, something called dysbiosis, it is still an open question how much of it is a cause of disease and how much is a consequence of it.
In brief
The gut microbiota is the population of microorganisms that lives in the digestive tract.
It helps keep the mucosal barrier intact, supplies nutrients such as vitamins, and protects against pathogens.
A neighborhood already lived in, not an empty lot.
The small intestine has acid, oxygen, antimicrobials and rapid transit; the colon, by contrast, supports a dense, diverse community of anaerobes.
Diet shapes it, and its adult composition does shift, but in dysbiosis cause still has to be separated from effect.
Sources (1)
- National Library of Medicine (PubMed Central), Biochemical JournalIntroduction to the human gut microbiota, Biochemical JournalPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
Updated