Aqua (Water) is the most common base ingredient in skincare formulations, serving as a solvent that dissolves water-soluble ingredients and provides the medium for emulsions. It carries active and functional components and influences product texture.
| Reported effect | How often | Notes |
|---|---|---|
| Skin irritation | Very rare | Pure water is essentially non-irritating; impurities or hardness minerals are more likely contributors than water itself. |
| Transepidermal water loss disruption | Rare | Repeated water exposure without occlusion may compromise the skin barrier in susceptible individuals. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.