What is the skin microbiome?

Human skin hosts billions of microorganisms — bacteria, fungi, viruses and mites — that form a complex ecosystem called the skin microbiome. Far from being harmful, the vast majority of these microorganisms play an essential role in protecting the skin, regulating its pH and maintaining its functional integrity.

Among the key inhabitants of the skin microbiome are Staphylococcus epidermidis, which produces natural antimicrobial substances, and Cutibacterium acnes, which is harmless in balance but whose excessive proliferation is associated with inflammatory acne.

Skin dysbiosis: when balance is broken

Skin dysbiosis is said to occur when this microbial balance is disrupted. This can occur after excessive use of antiseptic products or topical antibiotics, after intense UV exposure, due to chronic stress or hormonal fluctuations, or because of a pro-inflammatory diet.

During dysbiosis, Cutibacterium acnes proliferates disproportionately, protective bacteria decrease, and the skin becomes more susceptible to inflammation and imperfections. This imbalance is now recognised as one of the central factors in acne development, particularly chronic adult acne.

The probiotic approach: rebalance rather than eliminate

Conventional cosmetics has long sought to “kill” the bacteria responsible for acne. But this approach has limits: it indiscriminately destroys good and bad bacteria, promotes resistance and weakens the skin barrier.

The probiotic approach, on the contrary, seeks to restore microbial diversity so the skin regains its own defence mechanisms. Studies have shown that topical application of certain probiotic strains reduces the Cutibacterium acnes population and strengthens the skin's production of natural antimicrobial peptides.

Microbiome and diet: the gut-skin link

The skin microbiome is also influenced by the gut microbiome via the gut-skin axis. A diet rich in fibre, fermented foods and low in refined sugars promotes diverse and balanced gut flora, which is positively reflected on the skin. Conversely, a gut in dysbiosis can generate systemic inflammation that manifests notably through acne breakouts.

The actives that support the microbiome in Zactigis formulas

At Zactigis, microbiome health is at the heart of our approach. Our formulas include probiotic actives selected for their ability to rebalance the skin flora without aggressing it: lactoferrin, fermented white willow extracts, and strains selected for their effectiveness on imperfection-prone skin. This gentle but effective approach delivers durable results while respecting the skin's natural ecosystem.