Solvent

Water

INCI: Natural Moisturizing Factor (NMF), Deionized/Demineralized Water, Purified Water, Aqua/Water/Eau

Also known as: Natural Moisturizing Factor (NMF), Deionized/Demineralized Water, Purified Water, Aqua/Water/Eau

The most widely used cosmetic ingredient Typically appears as the first ingredient in skin care products

Best For Skin Types

All skin types

Usage Frequency

As directed on product packaging

What Is Water?

Water is the most frequently used cosmetic ingredient. Water in skin care products is almost always listed first on an ingredient label because it is usually the ingredient with the highest concentration in the formula. Water’s primary function in skin care formulas is as a solvent.

Despite claims of skin’s need for hydration and claims regarding special types of water, it turns out that water for skin may not be as an important ingredient as commonly thought. Only a 10% concentration of water in the outer layer of skin is necessary for softness and pliability in this part of the epidermis, known as the stratum corneum. Studies that have compared the water content of dry skin with that of normal or oily skin do not find a statistically significant difference in moisture levels between them.

Further, too much water can be a problem for skin because it can disrupt the essential substances in skin’s surface layers that keep it intact, smooth, and healthy-looking. As an example, recall how skin on your fingers and toes “prune” when you soak in the bathtub or other body of water for too long.

Benefits for Your Skin

How It Works

Water is the most frequently used cosmetic ingredient. Water in skincare products is almost always listed first on an ingredient label because it is usually the ingredient with the highest concentration in the formula. Water’s primary function in skincare formulas is as a solvent. Despite claims of skin’s need for hydration and claims regarding special types of water, it turns out that water for skin may not be as an important ingredient as commonly thought. Only a 10% concentration of water in the outer layer of skin is necessary for softness and pliability in this part of the epidermis, known as the stratum corneum. Studies that have compared the water content of dry skin with that of normal or oily skin do not find a statistically significant difference in moisture levels between them. Further, too much water can be a problem for skin because it can disrupt the essential substances in skin’s surface layers that keep it intact, smooth, and healthy-looking. As an example, recall how skin on your fingers and toes “prune” when you soak in the bathtub or other body of water for too long.

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