What is the Microbiome?

Micro” means something invisible to the naked eye, whilst “biome” refers to a collection of organisms that live in a particular habitat. Therefore, the microbiome is defined as the collection of microbes (and their genes) within a community.

These microbes include:

  • Bacteria
  • Archaea
  • Fungi
  • Protists
  • Viruses

Since these microbes are all over our body¹, we have different microbiomes, such as the skin, oral and gut microbiome – the latter of which is the most densely populated.

Why is the Microbiome Important?

Our gut microbiome plays an important role in digestion, nutrition and immunity2.

Overall, the microbiome contributes to vital mechanisms in the body, including:

  • Metabolism
  • Gut-brain axis
  • Synthesis of vitamins
  • Resistance to infection and inflammation
  • Production of short-chain fatty acids
  • Immune system development
  • Protection against pathogens
  • Control of fat storage

This fundamental role makes the microbiome important. It is a vital organ needed for us to function1. Every microbiome has their own signature of microbes that can strongly differentiate people’s profiles3 – just like fingerprints!

What is the Difference between the Microbiome vs Microbiota?

Often used interchangeably, there are subtle differences between your microbiome vs microbiota.

Overall, the microbiota definition describes all living microorganisms in a specific environment. The microbiome definition takes this further, to include the microbes and their genes.

In this way, the microbiome includes the microbiota and their genetic elements5.


  1. Huttenhower C, Gevers D, Knight R, et al. Structure, function and diversity of the healthy human microbiome. Nature. 2012;486(7402):207-214. doi:10.1038/nature11234
  2. Amon PSanderson I. What is the microbiome?
  3. Ursell LK, Metcalf JL, Parfrey LW, Knight R. Defining the human microbiome. Nutr Rev. 2012;70(SUPPL. 1):S38. doi:10.1111/j.1753-4887.2012.00493.x
  4. Berg, Gabriele et al. “Microbiome definition re-visited: old concepts and new challenges.” Microbiome vol. 8,1 103. 30 Jun. 2020, doi: 10.1186/s40168-020-00875-0

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