Fermented Skincare (Ferments)

Fermented skincare refers to products whose ingredients have been processed by microorganisms such as yeasts, bacteria or fungi before being added to a formula. This fermentation step transforms raw materials into new compounds, an approach with deep roots in East Asian, and particularly Korean and Japanese, beauty traditions.

During fermentation, microbes break down larger molecules into smaller ones and produce metabolites such as amino acids, peptides, organic acids and antioxidants. The idea is that these smaller, biologically active molecules may be easier for the skin to use, and that fermentation can create beneficial compounds not present in the original ingredient. The microbes themselves are usually removed or inactivated, so the finished product contains their by-products rather than live cultures.

• Recognisable ferment ingredients include galactomyces ferment filtrate, bifida ferment lysate and various lactobacillus ferments.
• Commonly featured in essences, serums and lightweight hydrating products.

Fermented ingredients are generally marketed for hydration, radiance, a smoother texture and support of the skin barrier. Some studies suggest ferment-derived compounds may have antioxidant and soothing properties, though the specific benefit depends heavily on the source material and the exact strains used, and marketing claims often outpace the available evidence. Ferments are usually well tolerated, but because fermentation yields complex mixtures, individuals with reactive skin or specific ingredient sensitivities may wish to patch test before regular use.