Demineralized (deionized) water is purified water with mineral ions removed, used as the primary solvent and base in many cosmetic and skincare formulations. It dissolves water-soluble ingredients and provides the medium in which other components are dispersed.
| Reported effect | How often | Notes |
|---|---|---|
| Skin irritation or dryness | Very rare | Water itself is essentially inert; transient dryness may occur with excessive washing or evaporation, not the ingredient directly. |
| Allergic reaction | Very rare | True allergy to purified water is not recognized; reactions are attributed to other formulation components. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.