Ronacare Urea Premium 100 g

Cosmetic Urea: Benefits in Cosmetics

Urea (carbamide) is a low-molecular-weight, water-soluble compound physiologically present in the stratum corneum of the skin. Urea is unique in that it simultaneously performs several scientifically proven functions: it is a natural component of NMF (Natural Moisturizing Factor), moisturizes by restoring the epidermal barrier, acts as a moderate enhancer for water-soluble substances, is used as a dose-dependent keratolytic, and also helps strengthen the skin's innate antimicrobial defenses.

Component characteristics and features of use

INCI: Urea

Molecular Formula: H2NCONH2

Molecular Weight: 60 Da

Synonyms  - Carbamide

CAS № 57-13-6

Appearance: urea is available in the form of crystals or granules. The appearance may vary depending on the batch.

Dosage: 1-5%, from 10% as a keratolytic. To prevent crystallization at high doses, we recommend using polyols (glycerin, sorbitol, propanediol).

Solubility: in water at temperatures no higher than 40°C (when heated to >50-60°C, it decomposes, forming ammonia and cyanic acid)

Avoid: pH increases above 8, combination with formaldehyde preservatives

Storage: Long-term storage is recommended in a dark place at a temperature of 15 to 25°C, protected from direct sunlight.

The Role of Urea in NMF

Urea has a low molecular weight, allowing it to easily penetrate the stratum corneum. It is naturally present in the stratum corneum and is part of the natural moisturizing factor (NMF - a complex of substances with water-retaining properties). Healthy skin contains 8 μg/cm2. In dry skin, urea levels are reduced to 3 μg/cm², while in damaged skin they are only 1.5 μg/cm². Very low concentrations are typical of aging skin, skin affected by eczema, and psoriasis. Skin with signs of atopic dermatitis is the most deficient in urea. As an osmotically active molecule, urea:

• binds water due to its high hygroscopicity
• maintains the plasticity of corneocytes by increasing their hydration
• prevents dehydration of the stratum corneum, increasing its elasticity
• indirectly reduces TEWL by restoring barrier function

Unlike hyaluronic acid, urea acts primarily within the stratum corneum rather than on its surface. Moreover, modern publications consider it an immunomodulatory component of the epidermal barrier.

The most important finding was that urea not only retains water but also regulates the expression of barrier proteins (filaggrin, loricrin, transglutaminase-1), thereby exerting a long-term restorative effect on the stratum corneum.

Cosmetics of Urea

• 2-5% - Moisturizing, NMF support
• 5-7% - Restoring the skin barrier, reducing TEWL and itching caused by dryness
• 10-15% - Moisturizing + moderate keratolytic (by weakening intercellular bonds)

Therapeutic dosages, not recommended for home use!

• 20-30% - pronounced keratolytic action through accelerated desquamation
• 30-50% - softening of hyperkeratosis, calluses, and nail lesions

Urea is used in the treatment of

• psoriasis, neurodermatitis and eczema,
• hyperkeratosis,
• ichthyosis,
• dandruff.

Urea has been shown to be well tolerated in vivo. Few side effects (temporary burning) were observed when applied to damaged skin at concentrations above 20%.

There is a direct correlation between decreased urea concentrations, increased transepidermal water loss (TEWL), and impaired skin barrier function. Clinical studies show a statistically significant increase in skin hydration after just 1-2 weeks of using creams containing 5-7% urea in xerosis and atopic dermatitis. Skin roughness and flaking are also reduced.

Suitable for areas such as elbows, knees, and feet, which are traditionally drier than other areas and lack regular moisture. It can be used in nail care products to soften cuticles. A low concentration of urea is used for dry skin in children over 3 years old. Urea cream is recommended for application to damp skin after a shower to enhance the moisturizing effect.

Urea as an enhancer

While not a chemical penetration enhancer (like propylene glycol or ethanol), it significantly facilitates the transport of hydrophilic components by increasing skin hydration and loosening keratin hydrogen bonds. This increases the diffusion of water-soluble substances and enhances the penetration of certain medications (e.g., corticosteroids and antifungals).

Suitable for areas such as elbows, knees and feet, which are traditionally drier than other areas and lack regular moisture. Can be used in nail care products, softens the cuticle. Low concentration of urea is used in case of dry skin in children over 3 years old. It is recommended to apply cream with urea to damp skin to increase the moisturizing effect.
 

Precautions

• avoid getting urea in the eyes, for this reason it is not recommended to use urea for eyelid care products,
• do not use if there are cracks, burns or wounds on the skin, inflammation,
• refrain from using in case of skin infections,
• in case of urea intolerance, the skin can respond with itching, irritation and rash.

Handmade cosmetics recipes, formulas and reviews

It is very difficult to create your own correct recipes if you are new to cream maker. And we are ready to help you with this. Go to the YouTube channel Beurre Cosmetic Kitchen, where we have already developed many recipes for handmade cosmetics and share the technology for making cosmetics with our own hands. And also you can check Blog from Beurre, where we share useful information about creating the right natural cosmetics.