What Is The Normal Microbiota Of The Body?
Bacteria are microorganisms that, despite their small size, play a key role in the functioning of the world. Scientists estimate that they represent 50% of the total biomass on the planet. Also, human beings have indispensable relationships with the bacteria that make up the normal microbiota.
In this article, we will explain what is the normal microbiota of the human body (also called microbiome) and what it is composed of.
What is a normal microbiota?
This interaction is a symbiotic relationship between the host and the bacterium, because both parties benefit from the relationship. Some of the benefits are:
- They produce vitamins and compounds that we cannot obtain from other sources.
- It protects the body from the colonization of other microorganisms that can be pathogenic, an aspect known as microbial antagonism.
Categories of human microbiota
The sum of all these populations gives rise to the normal microbiota, which we divide into two categories:
- Native microbiota: These are microorganisms that live in our body for an indefinite or long period of time. They participate in quantifiable physiological processes and have evolved together with the human species due to the fact that they have adapted to the environment we offer.
- Allochthonous microbiota: These microorganisms occur in any habitat and can occur in our body accidentally or temporarily. They do not participate in physiological processes, because their relationship with human beings is based on random encounters.
- Latent microbiota: This is the set of organisms that the host presents during its life cycle. In this case, we are the host. Populations do not fluctuate significantly and the symbiosis ratio is complete.
- Transient microbiota: This is the type that has continuous fluctuations and is usually not essential for the survival of the host. Factors such as time of year, age or medications can cause the transient microbiota to change.
What is the normal microbiota made of?
Scientists estimate that the intestinal microbiota contains more than 400 species of bacteria. Going further, it is estimated that for every human cell there are 10 bacteria in the body.
It is practically impossible to list all the significant species present in the normal microbiota. For this reason, there are lists of the most common species depending on the region of the body and depending on the common, occasional, rare or possible presence of the pathogen. The microbiota has a very clear representation in certain regions, such as:
- The skin, dominated by gram-positive bacteria
- The intestines, where the microbiota can weigh about 1.5 kilograms
- The vagina, where the primary genus is Lactobacillus (96% of bacteria in the area)
- The mouth, which has one of the most complex and heterogeneous microbiota in the body
