Kate Dyer is a microbiologist and skincare lover who uses her background in science to interpret skincare claims to share with readers of her blog, Beauty and the Biome. 

With so much in common, we were keen to find out more about Kate and her journey into the world of skincare and the skin microbiome. Read our Q+A with Kate below. 


Hi Kate, you state that the reason you started looking into skincare formulation was due to developing perioral dermatitis during your pregnancy, what was this experience like for you?

It was a challenging time. I was adjusting to life with a newborn while dealing with having painful and unsightly rashes around my mouth and eyes. I became incredibly self-conscious, and my biggest regret was that I didn't want to be photographed, so I missed out on having photos with my son while he was a baby.


Was this the main reason you began your blog 'Beauty and the Biome'?

Yes, this is the reason I started my blog. The many hours I spent breastfeeding used my background in microbiology to read scientific papers and research what causes the skin barrier to become comprised and what innate mechanisms the body has for healing this damage. This lead me to start researching and understanding how skincare ingredients work and interact with the skin and microorganisms living on the skin.

Once I could understand INCI lists, I was able to see how much money I had spent on products that were misleading with the ingredients they contained or that contained such small concentrations of active ingredients, they were unable to provide the benefits they were claiming.

I also became aware of how ingredients like added fragrance provide no skincare benefits and can actually be harmful to the skin long-term. Not only had I spent a lot of money, but I had also unknowingly been making my skin more sensitive by exposing it to these ingredients.

I decided to use the knowledge I gained along the way to help educate others on how skincare products are formulated and what ingredients they contain, as well as my personal experiences with each product.

What I discovered was that the health of the skin is completely reliant on the 10 trillion good bacterial living in the body and on the surface of the skin, known as the microbiome. This community of microorganisms fight acne-causing bacteria, produce hyaluronic acid and other factors to keep skin healthy, resistant and looking its best. By providing the proper nutrients to support the growth of these bacteria, the skin can repair itself and be it's healthiest and most resilient.


As stated in your blog title, a significant focus of your blog is looking at the connection between skincare and our microbiome and assessing if products do what they claim to do, which is really intriguing. What first piqued your interest in the microbiome?


I think it started with my appreciation of the fact that the microbiota account for 90% of our bodies cells, and only the remaining 10% are human. This really made me understand the importance of the symbiotic relationship we have with these organisms and the importance they hold for our physical and mental health. What I also love about this topic is that new information is emerging daily; there is still so much to learn.


Why is understanding the microbiome so important when it comes to skin health and skincare?


The gut-brain-skin axis is a term that defines how the microbiome is in constant communication with the brain and how any disharmony is often first noticed on the skin. Imbalances in the skin microbiota composition (dysbiosis) are associated with several skin conditions, like eczema, acne, allergies or psoriasis or sensitive skin, irritated skin or dry skin.


After a lifelong history of acne, sensitivity, dermatitis and redness, it was only once I restored my skin microflora and healed my gut through a healthy diet, was I able to see a dramatic improvement in my skin. My dermatitis cleared, my skin became less inflamed and reactive and I have only had the occasional breakout in the last several years.


What are the main ingredients that, according to your research, individuals should be wary of when it comes to harming our skin barrier or disrupting our microbiome?


There are many, as antimicrobial agents are still being misused in the skincare industry in order to treat conditions like acne. unfortunately, these are not selective and kill the beneficial bacterial, resulting in the disruption to the skin's pH balance, leading to a decrease in the diversity and numbers of helpful bacteria that are able to naturally outcompete with harmful bacteria for resources.


What roles do pre and probiotic skincare play when it comes to helping our microbiome?


Prebiotics can be plant sugars or oligosaccharides, and bacteria that have been grown and then attenuated (killed) are referred to as lysates. Both of these serve as a nutritional source for the resident bacteria that naturally colonise healthy skin. This helps reduce inflammation within the skin in the same way that has been shown by taking oral probiotic strains.

Probiotics in skincare are likely the most efficient way to effectively repopulate the microbiome. Probiotics like BLIS Q24®  that derived from a strain of Micrococcus luteus, a commensal resident of a healthy microbiome, are able to inhibit the growth of pathogenic bacteria associated with acne, impetigo and cellulitis.

Is there anything regarding the science of skincare formulation that people should be aware of coming from a degree-qualified microbiologist?

Be aware of any skincare calming to contain probiotics. There are many on the market, but they do not contain live bacteria and are using this term in a misleading way. What they do contain is prebiotics (like oligosaccharides) or postbiotics (like ferment lysates). While these are still beneficial for the skin, the lack of transparency in labelling is a potential concern. Unconditional Live Probiotic Hydration Serum is the only live probiotic skincare made in NZ and one of only a few available worldwide.


What is your current skincare routine and what changes have you made to it following your research into the formulation of products?

  • My skincare routine is simple and as gentle as possible, I don't exfoliate and try to keep the number of products I use to a minimum.
  • My morning routine is an oil cleanser, followed by an essence and a Vitamin C serum. I might use a hydrating or calming serum with hyaluronic acid or Centella asiatica if my skin needs extra care. I use Unconditional Live Probiotic Hydration Serum as my moisturizer and always use an SPF 45 or 50.
  • My evening routine is an oil cleanse, gentle cleanse, essence, serum, then Unconditional Live Probiotic Hydration Serum. Lately, I have been incorporating peptides into my routine as I'm starting to develop fine lines. I use a sheet mask weekly.
  • I only use low pH skincare, ideally, those that sit around pH 4.7, but I always avoid anything over pH 6. (Unconditional Live Probiotic Hydration Serum had a pH of 4.8 when I tested it).
  • I seek out ingredients that nurture the microbiome like prebiotics, probiotics and postbiotics.
  • I avoid sulphates in my cleansers and won't use any products that contain antimicrobial ingredients like alcohols, fragrances, phthalates, parabens or triclosan.
  • Always wear sunscreen, even during winter or when indoors. The sun is an overlooked enemy of the microbiome.

Live Probiotic Hydration Serum


What is your philosophy when it comes to skincare?

Nurture your microbiome. Most of the expensive skincare ingredients we are buying, like hyaluronic acid, lactic acid and acetic acid, are naturally produced by the microbiome within the layers of the skin. Why apply them topically and hope they are absorbed when these can be made for us where they can work their best.

What is the best piece of skincare and or beauty advice you have received?

Not everything happens overnight; results can be cumulative and take time to show on your skin. Be patient and don't look back with regrets; love the skin you have.