Avene Hydrance Optimale Light 40ml

DESCRIPTION

What It Does: Provides plant membrane sterol anti-inflammatory and barrier support with 5-alpha-reductase inhibition.

Why It's Used: Multi-function phytosterol combining barrier mimicry (identical to cholesterol structure) with anti-inflammatory and anti-androgenic activity for acne-prone and aging skin.

How It Works: Integrates into stratum corneum lipid bilayers analogous to cholesterol for barrier support. inhibits 5-alpha-reductase for dht reduction. inhibits nf-kb and cox for anti-inflammatory activity. cholesterol analog provides skin conditioning and membrane stabilization.

Typically Found In: Anti-inflammatory serums,anti-acne products,natural oils and butters (as unsaponifiable component)

TECHNICAL DETAILS

Primary Category: Active ingredient – phytosterol anti-inflammatory

Secondary Functions: Barrier cholesterol analog,5-alpha-reductase inhibition

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–3%

SOURCING & ETHICS

Vegan Status: Yes – from plant oils (soy, tall oil, avocado unsaponifiable)

Halal Status: Yes

Source Notes: Plant-derived, synthetic or animal-derived. verify source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Beta-sitosterol's structural identity with cholesterol (only one additional ethyl group at c-24) allows it to substitute for cholesterol in cell membrane bilayers and skin barrier lipid structures. this structural mimicry explains its barrier-supportive activity while its c-24 ethyl group subtly alters enzyme interactions, providing 5-alpha-reductase inhibition not seen with mammalian cholesterol.

Last Verified: Cosing database,bouic phytosterol review,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Delivers targeted skin-conditioning or bioactive benefits through a specific mechanism of action suited to the formulation's intended purpose.

Why It's Used: Specialty actives address specific skin concerns through targeted molecular mechanisms, providing efficacy beyond what base formulation ingredients alone can achieve.

How It Works: The bioactive compound interacts with specific molecular targets in skin cells or the extracellular matrix — enzymes, receptors, structural proteins, or signaling molecules — triggering beneficial biological responses.

Typically Found In: Serums,treatments,moisturizers,specialty products

TECHNICAL DETAILS

Primary Category: Specialty actives

Secondary Functions: Skin-conditioning,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.01–5%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Specialty active ingredient; check individual sourcing for vegan status.

SKIN COMPATIBILITY

Irritancy Rating: 1

Comedogenicity Rating: 0

Sensitivity Concerns: Low sensitization potential at recommended use concentrations.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Well-characterized cosmetic ingredient with established safety profile. generally non-irritating at typical use concentrations. suitable for leave-on and rinse-off cosmetics.

Works Well With: Niacinamide,hyaluronic acid,vitamin c,peptides

Avoid Combining With: Incompatible with oxidizing agents; check ph stability

SCIENTIFIC NOTE

Specialty actives typically work through enzyme inhibition (e.g., tyrosinase inhibition for brightening, mmp inhibition for anti-aging), receptor activation (e.g., retinoid receptors, ppar-γ for barrier genes), or transcription factor modulation (e.g., nrf2 for antioxidant gene upregulation). structure-activity relationships determine potency and selectivity.

Last Verified: Cosing eu database; pcpc cosmetic ingredient safety reviews; ingredient-specific safety and efficacy literature

Primary Sources: 2025-01-15

DESCRIPTION

What It Does: Provides transparent gel textures and thickening at very low concentrations via ph-responsive swelling.

Why It's Used: The most widely used gel thickener – provides crystal-clear, stable gels at concentrations as low as 0.1-0.5% with ph-controlled viscosity.

How It Works: Highly crosslinked polyacrylic acid remains tightly coiled at acidic ph. neutralization with naoh or triethanolamine ionizes carboxylic groups causing electrostatic repulsion that unfolds and swells the polymer coils, dramatically increasing viscosity. concentration-dependent thickening.

Typically Found In: Gels,serums,emulsions,sunscreens

TECHNICAL DETAILS

Primary Category: Functional ingredient – polyacrylic acid thickener

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–2%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Carbomer's ph-responsive swelling mechanism provides an elegant formulation control tool: a neutralized gel can be liquefied by ph reduction (adding acid) and re-thickened by reneutralization. this reversible rheology control allows two-phase products that mix on application without the need for mechanical emulsification.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides gram-negative focused preservation complementary to phenoxyethanol for comprehensive spectrum coverage.

Why It's Used: Phenoxyethanol complement — chlorphenesin's gram-negative and antifungal coverage complements phenoxyethanol's gram-positive activity for full-spectrum preservation at lower individual concentrations.

How It Works: 4-chlorophenol ether glycol disrupts bacterial and fungal membranes. strong gram-negative activity (pseudomonas, e. coli). good candida antifungal activity. used with phenoxyethanol for synergistic broad-spectrum coverage. ph stable 3-9.

Typically Found In: Comprehensive preservation systems,baby products (low concentration)

TECHNICAL DETAILS

Primary Category: Functional ingredient – glycerol ether preservative

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–0.3%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Eu max 0.3% cosmetics. good safety profile. synergistic combination with phenoxyethanol (0.3% pe + 0.1% chlorphenesin often equivalent to 1% pe alone).

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Chlorphenesin + phenoxyethanol synergy operates through a classic spectrum-filling combination: phenoxyethanol provides strong gram-positive antimicrobial activity while chlorphenesin provides gram-negative and antifungal coverage. the combination's minimum inhibitory concentration sum is subadditive (provides equivalent preservation at combined concentrations below what either alone would require) — textbook pharmacological synergy enabling lower total preservative load.

Last Verified: Cosing database,eu preservative annex v,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides a dry, weightless application vehicle that evaporates cleanly leaving actives and non-volatile silicones deposited on skin — eliminating the residual heaviness of conventional liquid carrier solvents.

Why It's Used: Cyclosiloxanes are the unique volatile silicone solvents that dissolve non-volatile silicones (dimethicone, cyclomethicone), organic uv filters, and lipophilic actives, providing the sensory-superior dry-touch application experience in premium formulations.

How It Works: Cyclosiloxane vapour pressure (d5 cyclopentasiloxane ~0.3 mmhg at 25°c) provides clean evaporation at body temperature. the cyclic ring structure provides lower boiling point than equivalent linear dimethicone, enabling faster evaporation while the ring conformation maintains the silicone's low surface energy for smooth application.

Typically Found In: Primers,antiperspirants,sunscreens

TECHNICAL DETAILS

Primary Category: Functional ingredient – emollient

Secondary Functions: Barrier sealing,softening

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–50%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Plant-derived, synthetic or animal-derived. verify source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Cyclopentasiloxane (d5) and cyclohexasiloxane (d6) are under eu regulatory review for potential environmental persistence (pbt assessment) — formulators should monitor eu regulation 2018/35 implementation for restrictions in wash-off products.

Last Verified: Cosing database,eu cyclosiloxane regulatory review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Glycerin pulls water from the environment and deeper skin layers into the outer skin layer (epidermis), boosting moisture levels and keeping skin soft, smooth, and plump.

Why It's Used: It is used in virtually every moisturizer, serum, and cleanser because it is highly effective at hydrating skin, is well-tolerated by all skin types, and enhances the texture and spreadability of formulations.

How It Works: As a humectant, glycerin forms hydrogen bonds with water molecules, trapping them in the skin. it also reinforces the skin barrier by integrating into lipid structures between skin cells.

Typically Found In: Moisturizers,serums,cleansers,toners,sheet masks,sunscreens,body lotions,shampoos,conditioners

TECHNICAL DETAILS

Primary Category: Humectant

Secondary Functions: Skin barrier support,emollient,solvent

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–30% (typical: 3–10%)

SOURCING & ETHICS

Vegan Status: Yes – plant-derived (coconut, soy, palm) or synthetic

Halal Status: Yes – when plant-derived or synthetic; verify source with supplier

Source Notes: Derived from plant oils via hydrolysis or saponification; synthetic versions also available. palm-derived glycerin carries sustainability concerns.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low; non-irritating at all standard concentrations

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Extremely rare allergic reactions; generally safe for all skin types including sensitive and baby skin

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Widely recognized as safe. ewg hazard score: 1. no significant concerns for irritation, sensitization, or toxicity at typical concentrations (up to 50%).

Works Well With: Hyaluronic acid,ceramides,niacinamide,panthenol,urea,peptides,retinol,ahas/bhas

Avoid Combining With: No known incompatibilities at standard concentrations

SCIENTIFIC NOTE

Glycerin is an endogenous skin component found naturally in the stratum corneum. aquaporin-3 channels in keratinocytes facilitate glycerin transport, making it integral to natural skin hydration pathways.

Last Verified: Cosing database,cir safety assessment,ewg skin deep,inci decoder

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides natural phospholipid emulsification with barrier-compatible delivery and liposome-forming properties.

Why It's Used: The most biologically authentic emulsifier – identical to cell membrane composition providing barrier-compatible delivery and liposome formation unavailable from synthetic emulsifiers.

How It Works: Phosphatidylcholine (pc), phosphatidylethanolamine (pe), phosphatidylinositol (pi) mixture provides hlb 7-12 for o/w emulsification. forms liposomal bilayers for active encapsulation. pc/pe/pi composition mirrors cell membrane for barrier-compatible delivery.

Typically Found In: Natural cosmetics,liposomal products,barrier repair,penetration-enhanced formulas

TECHNICAL DETAILS

Primary Category: Functional ingredient – natural phospholipid emulsifier

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–10%

SOURCING & ETHICS

Vegan Status: Conditional – soy lecithin (vegan); egg lecithin (not vegan)

Halal Status: Conditional – soy (halal); egg (verify)

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Lecithin's phospholipid composition mirrors the composition of the stratum corneum's own lamellar bodies that deliver barrier lipids to the skin surface. this structural mimicry allows lecithin-based delivery systems to integrate seamlessly with the barrier lipid structure, exploiting the same transport pathway the skin uses for its own lipid secretion.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Prevents microbial contamination and spoilage in cosmetic formulations.

Why It's Used: The benchmark cosmetic preservative – eu-permitted up to 1%, effective against virtually all cosmetically relevant microorganisms, and excellent tolerability.

How It Works: Phenol ring provides broad antimicrobial activity via disruption of bacterial and fungal cell membranes and inhibition of enzymatic activity. effective against gram-positive and gram-negative bacteria, yeasts (candida), and molds (aspergillus). activity ph range: 3-9.

Typically Found In: All cosmetic formulations as primary preservative

TECHNICAL DETAILS

Primary Category: Functional ingredient – broad-spectrum preservative

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–1% (eu max 1%)

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Eu cosmetics regulation max 1%. sccs assessed as safe at ≤1%. avoid use around eyes in baby products per some country regulations. ewg score: 4.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Phenoxyethanol's widespread adoption as the primary cosmetic preservative followed the phaseout of parabens from many formulations in the 2000s-2010s. despite having a comparable or better safety profile to parabens, it is often cited in 'free-from' formulations – a consumer perception issue rather than a scientific safety concern.

Last Verified: Cosing database,sccs opinion on phenoxyethanol,cir safety assessment

Primary Sources: 2026-03-12