The ingredient, explained
Water
Human studies examine repeated skin exposure to water.
Ingredient guide
What it is and what it does
Water supplies a liquid solvent for a formula. Ingredients that dissolve in water can be carried in this part of the product.
About this ingredient: CosIng identity and functions via Open Beauty Facts ↗ · European Commission ingredient function definitions ↗
- Antiplaque
- An oral-care role associated with controlling dental plaque.
- Skin conditioning
- A broad cosmetic role for maintaining skin condition. It does not identify a particular clinical benefit.
- Solvent
- Dissolves other ingredients in a formula.
Function definitions: European Commission ingredient function definitions (SCCNFP/0299/00, pages 16 to 20) ↗
Registry functions describe possible formulation roles, not results for a finished product. A dictionary entry is not an approval or a safety assessment.
A closer look
What the research shows
Human topical research
In 21 volunteers with experimentally irritated skin, repeated water exposure increased blood flow without a significant water-loss change. A separate 20-person study found increased water loss and pH after five days of forearm immersion in tap water.
What this does not tell us
These water-exposure experiments do not test water as an isolated active in a moisturiser. The skin condition and exposure schedule matter.
Sources for this summary. PubMed 9115917 ↗PubMed 25066831 ↗
Research review checked Oct 1, 2026
Bounded review of 104 local candidate records, selected relevant abstracts, and targeted exact-name primary-source searches. Not a systematic review.
Ingredient research is not proof that a product containing this ingredient works.
Read the 2 selected studies
Human topical research · n=21
Effect of water on experimentally irritated human skin. ↗
The British journal of dermatology · 1997
Human topical research · n=20
The effects of water exposure on biophysical properties of normal skin. ↗
Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digital Imaging of Skin (ISDIS) [and] International Society for Skin Imaging (ISSI) · 2015
Follow the formula
Products containing this ingredient
From the Serenfold edit. Linked by the ingredient list, without an efficacy ranking.
Names and identifiers
Registry identity
Aqua -EU-,Deionized Water,Distilled Water,Micromatrix Fractile AN,Onsen-Sui -JPN-,Purified Water
- INCI name on ingredient lists
- WATER
- CAS registry number
- 7732-18-5
- EC number
- 231-791-2
Sources for this ingredient record
- EU CosIng ingredient registry (via Open Beauty Facts taxonomy) ↗ · ODbL 1.0 (Open Beauty Facts database) · Recorded Aug 8, 2026
- European Commission ingredient function definitions ↗ · Recorded Sep 30, 2026