You are a superorganism, made up of many. 

Different parts of your body are home to different microbiomes, who all work together. There are five in fact – skin, gut respiratory, vaginal, oral) and the makeup of these vary from person to person.   

There are lots of things that effect your microbiome and its diverse makeup. Your age, diet, whether or not you take antibiotics or other drugs, the people, and animals, you interact with, where you live and potentially even your genetic makeup.  


Colonisation of the skin microbiome happens at birth, either when the baby enters the world through the birth canal, or from human skin when they are held and touched (in the case of C sections).  

The Hygiene Hypothesis 

Those that live in rural areas that interact a lot with soil and animals have different sorts of microbes than those in urban areas. They are more likely to be exposed to viruses, bacteria, or parasites and these help their immune systems to develop. In theory, exposure to these sorts of germs teaches the immune system not to overreact.  

There’s evidence that children who have grown up in sterilised environment, with less exposure to dirt and diverse bacteria, are more likely to have an immune compromised disorder such as asthma or eczema.   

Recent research on the Gut/Brain Axis indicates that microbial metabolites can even affect the brain, influencing our mood and mental health. 


What are the different types of microbes, and how do they behave? 

To keep things simple, we’ll group them into three categories: 

Passive Guests 

These are the commensal microbes which have little purpose, except to take up space which at least crowds out the more aggressive intruders.  They just quietly do their thing. 

Most of the microbes on our skin are passive guests, however sometimes they can turn on us, becoming pathogenic when they are over-abundant or invade other areas of the body.  

 The Bad Guys 

These are the pathogens which we all have in our bodies, the ones we are trying to destroy by doing things like brushing our teeth. We will never completely get rid of them so we have to work out how to at least keep them under control. 

Friendly Fellows 

Then we have the good guys, the symbionts. These are the ones that help us out and we want to keep around. They are mutually beneficial. You give them a nice environment to live in and they reward you with a healthy microbiome, resulting in a stronger skin barrier and immune system. Win-win.  

The Gut-Skin-Brain Axis


The Gut-Brain axis has long been a hot topic of research, with the gut dubbed the “second brain.”  

Now a new area of focus is emerging – the gut-skin-brain axis. Well, not actually that new, as nearly a century ago dermatologists Stokes and Pillsbury linked gastro problems with mood disorders and skin problems.  

The dermatologists found that 40% of those with acne had a low stomach acid called hypochlorhydria, a condition that causes bacteria to move from the colon into the small intestine (where they don’t belong). Untreated, this can lead to malnutrition and leaky gut.  

Stress and a diet high in processed foods have also been shown to slow down digestion in the gut, creating a shift in our microbiome. Bad bacteria beings to crowd out the good bacteria, creating inflammation in the gut, and compromising our intestine lining.  These toxins leak out from our intestines into our bloodstream, triggering inflammation…all the way to our skin. This means that if you are genetically susceptible to a skin condition (like acne or eczema) this inflammation trigger can lead to it.  

Put simply, the gut, skin and brain speak to each other and influence the immune systems response.  What does this mean for you? It means you should do what you can to feed the good bacteria, not the bad ones.  Look after your gut and you’ll be looking after your skin and brain too.  

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