Part 3 of our article series on the importance of the microbiome!

 

There’s a famous African proverb that says, ‘it takes a village to raise a child.’ The idea is that it takes an entire community to grow and sustain a human. We can all recognise the truth in those words when it comes to society, but they’re also a great way of understanding the community of microorganisms that live on our bodies and support us – the human microbiome!

The human microbiome is the catch-all term we use when talking about the many, many microbes that call our bodies home. Exactly how many, you ask? A million? Perhaps even a billion? Not quite. In fact, current estimates think that the average human adult has this many microbes living in or on their body:

39,000,000,000,000!

That’s 39 trillion, which is one big village for raising a human if you ask us. In fact, there are more cells belonging to independent organisms in the body than there are cells belonging to the body itself. These microorganisms perform vital functions for the body and make a huge contribution to keeping all of us healthy. In exchange, we provide a habitat to live and a constant source of nutrients – it’s a symbiotic relationship!

Skin has one of the most diverse and fascinating microbiomes to be found on the human body, and understanding how this system stays balanced – and what to do when things go wrong – is essential to keeping your skin strong, healthy, and youthful. That’s why we at LUMI simply never stop talking about it, as regular readers will know!

Today, we help you care for your own skin microbiome by taking a look at the different types of microorganism that inhabit it. We’ll be exploring the vital roles each element plays for their host, looking at what happens when things go wrong in the microbiome, and showing you how LUMI can help you keep your microbiome as happy and healthy as possible going forward. Let’s get started!

Brilliant Bacteria

When talking about the skin microbiome, bacteria are usually the main focus of discussion. As the most abundant microorganisms on the surface of the skin, bacteria play a key role in maintaining the health of both the microbiome and the skin itself.

Whilst different people and different areas of the body can host a wide variety of bacteria, four genera dominate proceedings: Corynebacterium, Staphylococcus, Streptococcus, and Cutibacterium. Remembering their names is not important, but each genus (a group of species) contributes something different to the body.

Some species of Corynebacterium, for example, help stimulate the immune system and make the surface of the skin inhospitable for dangerous pathogens, preventing them from freely multiplying and causing disease. Staphylococcus epidermidis has been shown to also assist in immune regulation and pathogen defence, as well as accelerating wound repair.

And that’s not all! Streptococcus improves skin structure and barrier function, whilst Cutibacterium species do everything from helping regulate skin pH levels to reducing oxidative stress, as well as fending off pathogens and modulating immune responses in a similar way to the other mentioned bacteria genera. It’s hard to overstate just how important bacteria are to our continued skin health!

Unfortunately, there is also another side to the skin microbiome. Sometimes things go wrong, and these microscopic allies of ours become microscopic enemies instead (at least for a while).

Some of humanity’s most common diseases spring from naturally present bacteria growing more quickly than they should, or getting into somewhere they shouldn’t – staph infections, strep throat, and acne (named after Cutibacterium acnes) being three prominent examples that all stem from the very same genera we have just been lauding!

When the microbiome is damaged, unbalanced, or otherwise not functioning properly, it is said to be experiencing dysbiosis. Dysbiosis of the skin microbiome is associated with a host of skin conditions, including the emergence of acne, atopic dermatitis, rosacea, and psoriasis, and rebalancing the environment should always be a key element of any skin treatment.

Harsh antibiotics that destroy the skin microbiome can fight bacterial overgrowth in the short term, but there is then nothing to stop this bare skin being recolonised by harmful species that were previously kept at bay. That’s why LUMI always believes in assisting and rebalancing bacteria, not simply scouring skin clear – but more on our skincare philosophy later on!

Valuable Viruses

Whilst most people these days know that not all bacteria are dangerous, and even that a lot of bacteria are very beneficial, the reputation of viruses is considerably more negative. This makes sense, because we usually only discuss viruses when they are making us sick. However, not only are viruses an entirely normal part of the human microbiome, but they’re also far more prevalent than you might realise, and have been shown to have beneficial effects on our skin and other microorganisms.

Remember the 39 trillion microbes present in the body? Whilst it was an impressive figure, it’s nothing compared to the amount of viruses present – an estimated 10000000000000. That’s almost thirty times more!

There is some debate about whether a virus counts as a microbe or as a living thing on its own or not. What we know for sure, though, is that viruses do not have their own cells, and instead burrow into other organisms’ cells – either into those belonging to complex systems, like humans, or into single-cell organisms such as bacteria.

How do viruses benefit our skin, though? By helping to regulate the bacteria found in the microbiome! For example, whilst Cutibacterium acnes is found on both healthy skin and skin suffering from acne, researchers in one study found more viruses present in bacteria living on healthy skin. The conclusions of that study suggested that viruses played a part in keeping bacteria levels in check, and that when viruses were no longer as present, acne symptoms increased.

Fantastic Fungi

When you think of fungi, you might picture giant toadstools in a forest, or portobello mushrooms on a dinner plate. But did you know that our skin is also colonised by fungi from birth? These microscopic species are distant cousins to the mushrooms we’re familiar with and play a vital role in maintaining the health of our skin and body as a whole.

Malassezia is the most dominant fungus genus on humans by far, with Candida also usually present. By taking up space and resources on the surface of our skin, Malassezia has been shown to protect skin from infection from pathogens such as Candida auris and Staphylococcus aureus, which cannot gain a foothold on the skin and grow freely.

This is a process called competitive exclusion, and it’s the reason that scouring skin of all microorganisms can be a very bad idea. Without an existing balanced microbiome, it’s much easier for invasive microorganisms to dominate, free from natural checks and balances!

Of course, like with bacteria, an overgrowth of Malassezia can itself become an issue. The fungus is heavily associated with seborrheic dermatitis (called dandruff in mild cases), and treatment often centres around anti-fungal therapy for affected areas to drastically reduce the amount of Malassezia present.

The fungus has also been shown to be more prevalent in severe atopic dermatitis cases, though it is thought that Malassezia is likely an opportunistic pathogen that potentially makes atopic dermatitis cases worse, rather than the root cause of issues.

…and Everything Else!

Between bacteria, viruses, and fungi, we’ve covered the vast majority of the microbes you’ll find within the skin microbiome, but there are a couple of outliers that it’s worth being aware of.

Archaea are single-cell micro-organisms that are often found in extreme environments. They were once thought to be a type of bacteria and share many similarities, but have since been separated into their own classification. The first archaea found on human skin were only found in 2013, and there is some debate within the world of microbiology over whether archaea should be considered a permanent part of the human skin microbiome.

Studies into the matter have thrown up vastly different results over the past decade, with levels of archaea varying wildly between experiments. There is some evidence that the varying levels of archaea found on the skin are due to changes in sebum levels (oiliness of skin) that occur as we age. The idea of a ‘skin archaeome’ and what it entails is likely to be a hot topic for scientific research over the next decade!

Demodex mites are tiny parasites that live on human skin, preferring areas with lots of sebum, such as the face and around hair follicles. Every single one of us has Demodex living on our bodies, and even though some might be alarmed by the idea, these miniscule arthropods are actually thought to benefit the body by eating dead skin cells and excess sebum.

Though, even if they are a beneficial parasite, we still wouldn’t advise searching on Google for a picture of them unless you’re particularly stout-hearted. We made that mistake the hard way, dear reader…

Just as with any other element of the microbiome, mites can contribute towards dysbiosis and skin issues. Research has shown that Demodex can play a part in several forms of dermatitis, as well as folliculitis and rosacea (skin reddening). Just as with bacteria, viruses, and fungi, Demodex become a problem for our skin and overall health when they are overrepresented in the microbiome.

Bring Back the Balance to Your Skin Microbiome with LUMI!

So, we’ve taken a look at the makeup of the human skin microbiome, explored the myriad benefits these microbes (and mites) bring to us, and also seen what can happen when things go wrong and dreaded dysbiosis strikes! If you’re anything like us, dear reader, then we’re sure you’ve got one question in your mind right now: how can I help keep my skin microbiome in tip-top condition?

Have no fear! Here at LUMI, the microbiome is always at the forefront of everything we do. We recognise the importance of keeping the skin’s microorganisms in harmonious balance, whether that is between different microbial populations or with the body itself!

Prebiotics are a great way to support beneficial microbiota. They function as a food source for bacteria and encourage the growth of certain beneficial strains. We’ve been making use of prebiotics in our creams and serums for well over a decade, and you’ll find them included in most of our products. Our Bio-Klinik Series was Estonia’s first hypoallergenic and prebiotic skincare range, and is perfect for those looking to rebalance and maintain the health and balance of their skin microbiome!

Because so many of the microorganisms on our skin survive on dead skin cells and excess sebum, it’s important to prevent microbiome overgrowth through regular exfoliation. The AHA-BHA acid blend found in our TUNDRA AHA-BHA Moisturising Cream  helps keep skin clear and clean of build-up, whilst not containing any ingredients that may destroy or otherwise upset the fragile peace of the microbiome.

Hyaluronic acid is not just a fantastic skin hydrator – it also supports the microbiome, too! We have so many products containing hyaluronic acid that it was hard to pick a favourite to showcase, but you can’t go wrong with our award-winning NAKED Hyaluronic Acid Multiserum, that combines niacinamide, the titular hyaluronic acid, prebiotics, and a host of other ingredients to create a serum that can do it all!

Remember, your skin microbiome is an incredibly beneficial ally, but it can also be a source of trouble if it’s not treated right. Be gentle on your skin, support beneficial microorganisms with our help, and above all… keep things balanced!

Ready to give your microbiome the help needed to stay healthy and balanced, so it can continue to protect and support you? Simply click any of the links above to be whisked away to individual product pages, or click here to see our entire range of microbiome-friendly skincare solutions!

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