Bacteria is on a redemption tour these days. Once-niche terms, such as “microbiome,” “probiotics,” and “prebiotics,” have gone mainstream, appearing in your skincare routine and A.M. yogurt alike. They all tie back to the bacteria that live in harmony on your skin. But what are these bacteria *actually* doing for you — and why is it worth thinking about them from time to time? Great questions! We’ll start with a cheat sheet:

  • The skin microbiome entails the 1,000+ types of microorganisms that live on skin
  • The bacteria on skin do everything from repair the skin barrier to boost the immune system
  • The microbiome is a layer of protection that encompasses your skin barrier
  • A healthy diet can help you maintain a healthy microbiome
  • Prebiotics, which serve as bacteria food, can help rebalance an imbalance microbiome

Now, let’s get into the nitty-gritty.

What is your skin’s microbiome?

There’s more to skin than what meets the eye. “Our skin is host to around a thousand microorganisms — bacteria, viruses, fungi — that collectively make up our skin microbiome,” says NakedPoppy research scientist Marisa Plescia. It’s skin-crawling stuff, literally — and it’s doing an important job keeping your skin healthy!

That said, the skin microbiome is incredibly important for the body at large, even playing a role in regulating your immune system. And for your skin specifically, “any of the microorganisms that are part of the skin microbiota are harmless, have a symbiotic relationship with the skin, and in some cases perform vital functions,” says Plescia. “The skin microbiota help to reinforce and even repair the skin barrier, and help to protect against infection and invasion by harmful organisms.”

And the influence of the skin microbiome goes far beyond your skin. “The pathways to understanding the interactions between the skin microbiota are diverse and complicated, but it has been shown that the skin microbiota actively play a role in immune response, wound healing, and can impact overall  human health,” says Plescia. All to say: The microbiome is super-important.

What does the skin microbiome do?

Not all bacteria are created equal, and on the surface of your skin, they can have many different roles. “Some signal the skin to produce healthy lipids, some digest and regulate oil production, some feed off of dead skin cells, and others regulate the bad bacteria and fungus,” says NakedPoppy skin specialist Tara Parenti.

The microbiome is also considered part of your skin’s protective barrier, and closely linked to the acid mantle. The acid mantle is a super-thin layer that sits on top of your moisture barrier and lends additional protection against outside aggressors. “The microbiome is very much dependent on the acid mantle being at a stabilized pH, which is slightly acidic,” says Parenti. When that’s the case, your skin is able to get the maximum protection.

What can throw off your skin microbiome

All of those beneficial functions sound great (and they are!), but they’re the result of a balanced skin microbiome. That balance can be thrown off, with less helpful bacteria overpowering beneficial bacteria, by anything that impacts your skin barrier, such as over-cleansing and other aggressive skincare habits.

That opens a Pandora’s Box of issues. “From common acne to worse skin disorders such as atopic dermatitis, skin disorders often have some sort of microbial correlation,” says Plescia.

Sometimes, the imbalance is more systemic. Take atopic dermatitis, or eczema. “Atopic dermatitis, or eczema, which results in red and itchy skin, also seems to be highly connected to the skin microbiome,” Plescia explains. The same goes for C. acnes bacteria, which is responsible for — you guessed it — acne.

How to balance your microbiome

The good news is that your microbiome, delicate though it may be, can usually self-regulate, so caring for it doesn’t require a ton of effort. “Our body functions best at homeostasis, a process that keeps things in your body at a steady state — and thus even with the skin microbiome, our body does a great job at maintaining,” says Plescia. To give your body a hand, follow these guidelines:

  • Wash with a gentle, sulfate-free cleanser, such as NakedPoppy Refresh Foaming Cleanser or Nourish Cream Cleanser, to maintain an optimal pH for your skin’s acid mantle.
  • Stick with a healthy diet, since your gut microbiome is connected to your skin microbiome. Think: vegetables and lots of water.
  • Slow down on antibacterial products. “Antibacterial products are definitely needed, especially during a time like COVID, but overuse can also produce some harm to your balanced skin microbiome,” Plescia explains. Opt for soap and water when available, and don’t slather on  hand sanitizer if you haven’t touched anything.

Then, there are the bacteria — or bacteria-related ingredients, to be more specific — in your skincare products. While probiotics, which are live bacteria cultures, have gotten the most attention, their efficacy in skincare is a little shaky. For instance, it’s hard to say whether the bacteria is actually alive when it makes it to your skin, and how well it meshes with the unique composition of your microbiome.

Prebiotics, which serve as bacteria food, have more traction. “Prebiotics can affect the skin microbiome by stimulating the growth of certain species, thereby promoting health benefits in the host,” Plescia says. They may also help you maintain a healthy, normal skin microbiome. For a boost of prebiotics, Parenti recommends mixing 54 Thrones Kahina Lava Cleansing Mask with apple cider vinegar and raw honey — two natural sources of prebiotics — instead of water to hydrate and nourish skin.

Possibly the best thing about your microbiome? Less is often more, and in most cases, the bacteria that make up your microbiome can take care of themselves — giving you one less thing to think about.

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