The Retinol Serum

DESCRIPTION

What It Does: Softens and conditions skin by integrating into sc lipid bilayers, delivers essential fatty acids (oleic, linoleic, linolenic) for barrier lipid synthesis, and provides rich, non-stripping moisturisation.

Why It's Used: Natural carrier oils provide the closest compositional match to endogenous sc lipids, delivering emolliency through genuine barrier integration rather than simple surface occlusion.

How It Works: Fatty acid triglycerides partition into sc lipid bilayers — oleic acid (c18:1) provides fluid, emollient integration; linoleic acid (c18:2) acts as essential ceramide precursor; saturated fatty acids provide more occlusive barrier reinforcement.

Typically Found In: Moisturisers,facial oils,natural skin care

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%–100%

SOURCING & ETHICS

Vegan Status: Conditional

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

Essential fatty acids — linoleic (c18:2, n-6) and α-linolenic (c18:3, n-3) acids — cannot be synthesised by the body; topical delivery through carrier oils provides direct substrate for ceramide and eicosanoid biosynthesis in the epidermis.

Last Verified: Cosing database,butyrospermum parkii butter carrier oil botanical review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides documented cosmetic activity from c12-16 alcohols.

Why It's Used: C12-16 alcohols delivers formulation value through its specific biological activity and established safety and efficacy.

How It Works: Source: c12-16 alcohols. mechanism: documented in cosmetic literature. safety: cosing-reviewed. standard cosmetic use concentrations.

Typically Found In: Skin care formulations,active products

TECHNICAL DETAILS

Primary Category: Active ingredient – antioxidant

Secondary Functions: Free radical scavenging,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–5%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

C12-16 alcohols provides cosmetic activity through its characteristic mechanism. at standard concentrations it delivers documented biological activity with an established safety profile from cosmetic science literature and regulatory review.

Last Verified: Cosing database,c12-16 alcohols technical literature

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Lightweight, stable emollient that solubilizes oil-soluble actives for excellent delivery without greasy feel.

Why It's Used: Universal lightweight emollient base and solubilizer for oil-soluble actives in serums and low-viscosity formulations where mineral oil or petrolatum would be too heavy.

How It Works: Medium-chain length provides ideal balance of spreading coefficient, penetration rate, and barrier-sealing properties. excellent solubilizer for vitamin e, retinoids, and other lipophilic actives.

Typically Found In: Serums,facial oils,sunscreens,anti-aging products,hair products

TECHNICAL DETAILS

Primary Category: Active ingredient – medium-chain triglyceride emollient

Secondary Functions: Active solubilizer,spreading agent

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 – from coconut/palm kernel oil

Halal Status: Yes

Source Notes: Fractionated by hydrolysis and re-esterification of coconut oil. only c8 and c10 fatty acids retained.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – very low; medium-chain length generally non-comedogenic

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

Mct oil's medium-chain length (c8/c10) provides superior oxidative stability vs longer polyunsaturated chains and better skin aesthetics (lighter, less greasy) vs longer chain emollients (c16/c18). excellent solubilizer for retinoic acid, tocopheryl esters, and other lipophilic actives.

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

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Hydrates by forming a water-shell around skin biomolecules, stabilises cellular membranes against heat/uv stress, and reduces inflammatory cytokine release in stressed skin.

Why It's Used: Provides dual humectancy plus cellular protection — unique among humectants for its documented ability to stabilise skin proteins and membranes against uv and environmental stress, not just attract water.

How It Works: Ectoin's tetrahydropyrimidine ring forms an ordered hydration shell around proteins, lipid bilayers, and dna through kosmotropic water structuring. this preferential hydration excludes denaturants and uv-stress mediators from biomolecule surfaces while simultaneously providing humectant moisture binding.

Typically Found In: Sensitive skin,uv protection actives,anti-inflammatory

TECHNICAL DETAILS

Primary Category: Functional ingredient – humectant

Secondary Functions: Tewl reduction,skin plumping

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

Halal Status: Yes

Source Notes: Synthetic or naturally derived. excellent aqueous solubility.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; suitable for all skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Ceramides,emollients,occlusives,glycerin,hyaluronic acid

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Extremophile bacteria accumulate ectoin at up to 15% intracellular concentration to survive 100°c temperatures and extreme salinity — the same biomolecule protection mechanism applies to human skin cells at cosmetic concentrations.

Last Verified: Cosing database,ectoin extremophile anti-stress clinical 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 antioxidant protection from reactive oxygen species, reduces inflammatory cytokine production in skin, and conditions skin through the plant's phytochemical complex.

Why It's Used: Natural origin narrative, traditional use heritage, and multi-functional phytochemical profile supporting concurrent skin care claims from one ingredient.

How It Works: Polyphenols, terpenoids, and alkaloids scavenge ros via h• donation, inhibit nf-kb or cox-2 inflammatory pathways, and interact with skin surface proteins for conditioning.

Typically Found In: Botanical skin care,natural products

TECHNICAL DETAILS

Primary Category: Active ingredient – antioxidant

Secondary Functions: Free radical scavenging,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–10%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Plant secondary metabolites evolved as photoprotectants and antimicrobials — mechanisms directly applicable to cosmetic antioxidant and anti-inflammatory activity in human skin.

Last Verified: Cosing database,glycine soja oil botanical review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides elegant dry-touch emolliency with excellent solubilisation for active ingredients.

Why It's Used: Premium emollient solvent — octyldodecanol's branched c20 structure provides a uniquely dry, elegant emollient character with exceptional compatibility for challenging actives.

How It Works: Branched c20 fatty alcohol provides dry, non-greasy emolliency. excellent solvent for fat-soluble vitamins, retinoids, uv filters, and flavour compounds. lower viscosity than longer-chain fatty alcohols for elegant application. very good spreading coefficient for uniform application.

Typically Found In: Premium skincare,sunscreens,vitamin delivery systems

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%–20%

SOURCING & ETHICS

Vegan Status: Yes – from c10 alcohols via guerbet reaction (plant-derived)

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

Octyldodecanol is produced via the guerbet reaction — a base-catalysed self-condensation of two c10 alcohol molecules (decanol) yielding the branched c20 2-octyldodecanol. this reaction produces a highly branched structure that prevents crystallisation (liquid at room temperature), providing liquid-state emolliency with a completely different tactile profile than the waxy feel of linear c20 fatty alcohols.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides humectant and solvent functionality from sustainable corn-based fermentation.

Why It's Used: Bio-based propylene glycol alternative from renewable corn — propanediol provides equivalent functionality to propylene glycol with sustainable renewable feedstock and superior skin feel.

How It Works: Two oh groups provide humectant water binding. excellent solvent for fragrances, actives, and preservatives. mild antimicrobial from diol structure for preservative system boosting. renew corn fermentation origin (dupont zemea process). better skin feel than propylene glycol — less sticky.

Typically Found In: Virtually all cosmetic categories as pg alternative

TECHNICAL DETAILS

Primary Category: Functional ingredient – humectant

Secondary Functions: Tewl reduction,skin plumping

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–20%

SOURCING & ETHICS

Vegan Status: Yes – from corn sugar fermentation

Halal Status: Yes

Source Notes: Synthetic or naturally derived. excellent aqueous solubility.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; suitable for all skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Ceramides,emollients,occlusives,glycerin,hyaluronic acid

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Propanediol's dupont tate & lyle bio products 'zemea' process ferments corn sugar to 1,3-propanediol using engineered e. coli — one of the first commercially viable bio-fermentation routes to a cosmetic diol previously made only from petroleum. the renewable route produces chemically identical 1,3-propanediol while reducing carbon footprint by approximately 40% vs petrochemical synthesis.

Last Verified: Cosing database,dupont tate & lyle zemea technical data,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides endogenous-skin-identical emolliency with exceptional stability and skin compatibility.

Why It's Used: The most skin-compatible emollient – chemically identical to human sebum squalene component with outstanding tolerability across all skin types.

How It Works: Fully saturated hydrocarbon with zero oxidation sites provides exceptional stability unlike squalene's 6 double bonds. integrates into stratum corneum lipid bilayers with near-perfect biocompatibility. provides antioxidant protection to formulation via radical quenching.

Typically Found In: Facial oils,serums,non-comedogenic moisturizers,luxury body care

TECHNICAL DETAILS

Primary Category: Functional ingredient – emollient

Secondary Functions: Maximum biocompatibility,antioxidant stabilizer,non-comedogenic

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–100%

SOURCING & ETHICS

Vegan Status: Conditional – plant-derived (sugarcane, olive) preferred; shark liver-derived being phased out

Halal Status: Yes – plant-derived

Source Notes: Sustainable plant-derived squalane from sugarcane fermentation (amyris) or olive oil fractionation is preferred over shark liver-derived. chemically identical regardless of source.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

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

Squalene constitutes approximately 12-15% of human sebum – the highest proportion of any skin lipid. topical squalane (stable, hydrogenated form) replenishes this abundant endogenous skin lipid. the complete absence of oxidizable double bonds (unlike squalene's 6 double bonds) eliminates the pro-oxidant concerns of natural squalene oxidation.

Last Verified: Cosing database,huang et al. squalane review,cir safety assessment

Primary Sources: 2026-03-12