The term “microbiome” is becoming more common.  There isn’t a day that goes past when an article in the press refers to the “microbiome” or “microbiota”.  What exactly are they?  And what do they do?

Microbiota is a term that is given to microorganisms that live on or in the body.  These can range from the beneficial bacteria to yeasts, parasites, viruses and fungi and can include the not so beneficial microorganisms as well.  The term microbiome refers to the collection of microorganisms and their genetic material.

The human body carries trillions of tiny little microorganisms; in fact they outnumber human cells! These little microbes can be located on the skin, in the mouth, in the vagina but the largest proportion can be found in the gut.  Research into the microbiome has flourished over the years and it has shown that each person has their own very unique balance of microbes, this is linked to our DNA, our environment and the type of food eaten.  Another finding is that each area of the body has its own very specific balance of microorganisms and that areas can differ greatly.  Scientists are now fining that individual strains of bacteria, or other microbes, have very specific functions within the body.

So, what do they do?

The microbiota have many roles to play within health and their importance in good health is becoming more well known.  Some of their functions include:

  • Synthesis of vitamins – gut microbiota are able to synthesise B vitamins including folates, riboflavin, thiamine and biotin.  They also produce vitamin K.
  • Digest some forms of fibre – fibre is essential for good bowel health and one of the reasons it is so beneficial is because the gut microbiota can produce enzymes that are able to ferment some forms of fibre.  This releases compounds called Short Chain Fatty Acids (SCFA’s) and these are known to help keep a healthy gut lining and aid in inflammatory bowel conditions.
  • Neurotransmitter balance – neurotransmitters such as serotonin, dopamine, GABA and acetylcholine are all produced by the gut microbiota.  These neurotransmitters play a role in mood, motivation, memory, relaxation and stress responses.  The gut has its own nervous system – called the Enteric Nervous System (ENS) and it has been found that the gut microbiome can influence the brain and vice versa.
  • Immune support – a large proportion of our immune tissue resides in the gut, 70%-80% in fact, there is no wonder then that scientists have found that the microbiome have a very large role to play in immune health.  Poor gut health has been shown to be associated with an increase in the development of auto-immune disorders.  How the microbiome interacts with the immune system is complex and research into the benefits of these tiny microbes is ongoing.

The benefits of the microbiome extend to beyond the gut and skin microbes help to maintain natural defences against unwanted pathogens, bacteria in the mouth have been shown to help with dental health and vaginal microbes are vital for inoculating a baby as it passes through the vaginal canal during birth.

There can be many foods that alter the levels and balance of the gut microbiome and eating a good selection of fermented foods or prebiotics can help to support good health.