Milk peptides are protein fragments derived from milk proteins (such as casein) used in skincare for moisturizing, soothing, and signaling effects that may support skin barrier function and a smoother appearance. They are typically incorporated as functional actives in anti-aging and hydrating formulations.
| Reported effect | How often | Notes |
|---|---|---|
| Mild skin irritation or redness | Uncommon | Usually transient and related to overall formulation rather than the peptide alone. |
| Allergic contact dermatitis | Rare | Possible in individuals sensitized to milk proteins; patch testing advised for those with dairy allergies. |
| Contact urticaria | Very rare | Reported in highly milk-protein-sensitive individuals. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.