Dysbiosis and your gut microbiome

Author: Dr Ken McGrath and Hayley Parcell

14 July 2020 Education Health Conditions Latest Science

There has been so much interest in the gut microbiome in the past few years, that by now you’re probably aware that looking after the bacteria in your gut is an important part of looking after your health. You may have even heard the term “dysbiosis” used to describe an imbalance in the gut. But what does this term actually mean?


What is dysbiosis?

Dysbiosis is a term used to describe a microbial imbalance or dysfunction on or inside the body, such as an impaired microbiome. It can be used to describe an imbalance in any microbial community, including those that live on your skin, in your reproductive tract, in your mouth, small intestine, or your large intestine. This means it is a general term to describe when a microbial community isn’t able to do the things that a healthy community would usually be able to do1.


Is dysbiosis real?

The idea of dysbiosis has been debated in detail, and while it serves as a general term for an imbalanced microbiome, some medical professionals apply caution to using this term. The reason is that until we fully understand what a “healthy” microbiome looks like, it is impossible to know what an unhealthy or dysbiotic microbiome would be. Currently, the term “dysbiosis” is a buzz word generally used to describe the likelihood that someone’s gut microbiome is contributing to poor health.

Researchers have previously highlighted that the microbiomes of healthy people can look dramatically different from one person to the next, in terms of the types of species present, and hence to define dysbiosis on a species-level may not make sense2.

In fact, Microba’s data supports that view – each and every person has their own unique combination of organisms, and the species you do or do not have won’t necessarily identify whether your gut might be out of balance (with the exception of some pathogenic species).

To understand if there is an imbalance in your gut, you need to look at the function of the microbiome – what those organisms are actually doing.


Prebiotic foods to improve gut health.

Why are prebiotics important for your gut health? Read the blog.


Species vs Functional Dysbiosis

When it comes to understanding your microbiome, there are two important elements to understand:

1) The species that are present, and

2) The different functions that they can perform.

We know that each person has a unique combination of species in their gut, and so to say that a healthy gut includes a defined list of species would not be correct. However, now that scientists have the technology available to look at the functions of those bacteria – i.e. not who they are, but what they can do – we start to see more consistent patterns between healthy people. This means that dysbiosis is not so much about which species are out of balance, but which functions are out of balance.  What we’re seeing is that healthy people’s gut microbiomes tend to perform functions associated with health, like producing short-chain fatty acids3 and vitamins4 and are less likely to produce substances linked to disease like TMA5, hydrogen sulphide6 and the inflammatory compound lipopolysaccharide / LPS7. Generally, a healthy microbiome has a beneficial balance of these functions, while the gut microbiome’s of individuals with health conditions such as diabetes, inflammatory bowel disease and mental health disorders, have a microbiome that is capable of producing more of the harmful and inflammatory substances and often less of the beneficial substances that contribute to good health.

Therefore, it is the imbalance in those functions that tends to be an indicator of dysbiosis, rather than the species themselves.


What does functional dysbiosis look like?

Because the gut microbiome has been shown to be connected to so many different health systems, including the cardiovascular, gastrointestinal, metabolic, and nervous systems, evolving research indicates that different forms of dysbiosis could manifest in different ways, perhaps even unique to a particular condition.

It is anticipated that the degree of functional dysbiosis may vary dramatically from one condition to the next. As an example, someone suffering from reduced mental clarity or dermatitis may have several minor imbalances that may contribute overall to their condition in multiple ways.8,9. For others, there may be more specific imbalances in only one or a few areas, which contribute to very specific conditions like cardiovascular health5 or gastrointestinal disorders like IBS.

Microba’s research into the functional imbalances of specific health conditions is rapidly developing and, in the future, may contribute to our understanding of different types of functional dysbiosis.

What can I do about it?

If you’re concerned about any aspect of your health, including how your gut microbiome may be contributing to your health, the best place to start is with a qualified healthcare professional. They can investigate your health and work out if there are any major underlying conditions that might be cause for concern.

To investigate your microbiome in more detail and begin to understand if your gut might be contributing to your health, you can take a microbiome analysis that looks at the functional aspect of the microbiome, to see if you have any signs of possible functional dysbiosis. It’s crucial to understand that most gut analyses will only report on the types of bacteria present, and won’t tell you about the function.

To learn more about how your gut microbiome is functioning, you need to use a microbiome analysis that uses a technology called metagenomics,  to understand if any functional aspects may be out of balance.

By doing this, you can start to take A.I.M. with your gut health by:

  • Assessing the microbiome, to understand your gut and identify any areas that might indicate dysbiosis;
  • Implement changes to your diet and lifestyle to shift your microbiome to address any areas of concern (Microba’s reports include personalised prebiotic foods which will support improved gut microbiome health);
  • Monitor your progress and re-test as needed to adjust your course and optimise your gut health.

Interested in looking at your gut microbiome? Check in with your healthcare professional. Read more.

Microba has partnered with a network of healthcare professionals that can help you understand your gut and how it might be contributing to your health – click here to find out more.

This microbiome test is not intended to be used to diagnose or treat medical conditions. A full disclaimer is available here


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