A recent study in the Journal of Investigative Dermatology reveals that certain skin bacteria, like Staphylococcus epidermidis, may serve as a natural form of sunscreen.

These microbes produce an enzyme called urocanase, which breaks down cis-urocanic acid—a molecule activated by UVB exposure that can suppress skin immunity and trigger inflammation—into harmless substances, reducing its harmful effects.

The research underscores the protective role of the skin microbiome, not only in defending against UV damage but also in regulating immune responses. These insights could lead to future treatments designed to boost or mimic this natural microbial shield.