Kefiran is an exopolysaccharide produced by lactic acid bacteria during kefir fermentation, used in skincare as a hydrating, film-forming and skin-conditioning agent with reported antioxidant and soothing properties. It supports moisture retention and skin barrier function in topical formulations.
| Reported effect | How often | Notes |
|---|---|---|
| Mild skin irritation or redness | Rare | Generally well tolerated; transient irritation possible in sensitive skin. |
| Contact allergic reaction | Very rare | Sensitization to fermentation-derived components is uncommon but theoretically possible. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.