OUAI Leave In Conditioner

DESCRIPTION

What It Does: Provides antioxidant protection from reactive oxygen species, reduces inflammatory cytokine production in skin, and conditions skin surface through the plant's secondary metabolite complex.

Why It's Used: Chosen for its natural origin narrative, traditional use heritage, and multi-functional phytochemical profile that supports several concurrent skin care claims from one ingredient.

How It Works: Polyphenols, terpenoids, and alkaloids in the oil scavenge ros via hydrogen atom transfer, 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: Yes

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 uv photoprotectants and antimicrobial agents — mechanisms that directly translate to cosmetic antioxidant and anti-inflammatory activity in human skin.

Last Verified: Cosing database,adansonia digitata seed oil botanical review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides nmf-type humectant moisture retention and skin conditioning.

Why It's Used: Simple, well-tolerated nmf amino acid humectant for skin conditioning formulations.

How It Works: Small methyl side chain contributes to protein hydrophobic core but as free amino acid provides direct humectant activity via amino and carboxyl groups. converted to pyruvate for cellular atp production via gluconeogenesis.

Typically Found In: Nmf moisturizers,skin conditioning products

TECHNICAL DETAILS

Primary Category: Active ingredient – amino acid

Secondary Functions: Nmf component,cellular energy

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–5%

SOURCING & ETHICS

Vegan Status: Yes – plant-derived or synthetic

Halal Status: Yes

Source Notes: Fermentation-derived or synthetic. natural skin component.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; endogenous skin molecule.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. natural skin nmf component. ewg score: 1.

Works Well With: Hyaluronic acid,ceramides,peptides,other amino acids

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Free alanine is among the most abundant amino acids in the stratum corneum nmf, where it contributes to the aqueous phase hydration that keeps the stratum corneum flexible and functional.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

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,argania spinosa kernel oil carrier oil botanical review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Conditions skin, attracts moisture, supports wound healing, and improves microcirculation via no synthesis.

Why It's Used: Multi-functional amino acid for skin hydration, conditioning, and wound healing in peptide and nmf formulations.

How It Works: Guanidinium group binds water (humectant). substrate for nitric oxide synthase (enos) producing nitric oxide that vasodilates capillaries improving skin nutrition. stimulates fibroblast proliferation for wound healing.

Typically Found In: Anti-aging serums,wound healing products,nmf moisturizers,scalp treatments

TECHNICAL DETAILS

Primary Category: Active ingredient – amino acid

Secondary Functions: Wound healing,microcirculation,nmf component

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–5%

SOURCING & ETHICS

Vegan Status: Yes – plant-derived or synthetic

Halal Status: Yes

Source Notes: Fermentation-derived or synthetic. natural skin component.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; endogenous skin molecule.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. natural skin nmf component. ewg score: 1.

Works Well With: Hyaluronic acid,ceramides,peptides,other amino acids

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Arginine is a conditionally essential amino acid in wound healing where local demand exceeds synthesis capacity. topical arginine provides the nos substrate locally for no-mediated vasodilation and immune cell function in healing tissue.

Last Verified: Cosing database,cir safety assessment,witte & barbul arginine wound healing review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Delivers characteristic cosmetic function at recommended use concentration.

Why It's Used: Selected for functional contribution and formulation compatibility supported by cosmetic science and regulatory safety data.

How It Works: Works through the mechanism of its molecular class — physicochemical or biological interaction with skin proteins, lipids, or receptors as documented in peer-reviewed cosmetic literature.

Typically Found In: Skin care formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – cosmetic active

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%–10%

SOURCING & ETHICS

Vegan Status: Conditional

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

Butyloctanol has an established safety and efficacy profile within the cosmetic regulatory framework at standard use concentrations.

Last Verified: Cosing database,butyloctanol technical literature

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: Provides gla anti-inflammatory activity for eczema and inflammatory skin conditions.

Why It's Used: The most clinically studied gla oil for eczema – clinical evidence for improved skin barrier function, reduced itch, and inflammation in atopic dermatitis patients.

How It Works: Gla (8-10%) provides anti-inflammatory pge1 precursors. high linoleic acid (72-74%) repairs barrier ceramide synthesis. combined anti-inflammatory + barrier repair addresses the dual pathophysiology (barrier dysfunction + immune dysregulation) of atopic dermatitis.

Typically Found In: Eczema products,barrier repair formulations,anti-inflammatory skin care

TECHNICAL DETAILS

Primary Category: Functional ingredient – emollient

Secondary Functions: Gla anti-inflammatory,eczema support,barrier repair

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 oenothera biennis seeds

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 – very low

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

Multiple clinical trials demonstrate evening primrose oil supplementation (topical and oral) significantly reduces tewl and eczema severity scores in atopic dermatitis. the dual mechanism (gla anti-inflammatory + linoleic acid barrier repair) addresses both the immune and barrier aspects of eczema simultaneously.

Last Verified: Cosing database,bamford et al. epo atopic dermatitis meta-analysis

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 nmf amino acid skin conditioning and collagen-constituent support.

Why It's Used: The collagen amino acid — glycine is the most abundant amino acid in collagen (every third residue in the triple helix is glycine) making topical glycine the most physiologically relevant collagen-support amino acid.

How It Works: Nmf component via zwitterionic water retention. collagen triple helix requires gly-x-y repeat where glycine's small size allows close packing. wound healing via fibroblast glutathione synthesis support. anti-inflammatory via glycine-gated chloride channel activation (inhibitory neuromodulator).

Typically Found In: Skin conditioning products,wound healing,nmf moisturisers

TECHNICAL DETAILS

Primary Category: Active ingredient – simplest amino acid

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%–5%

SOURCING & ETHICS

Vegan Status: Yes – fermentation or 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

Glycine's mandatory presence at every third position in collagen's triple helix (gly-x-y repeat) arises from its unique zero side-chain structure — only glycine is small enough to fit at the sterically restricted centre of the triple helix where the three polypeptide chains cross. no other amino acid can substitute for glycine in the collagen triple helix without disrupting the structure, making glycine irreplaceable in collagen biology.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides nmf conditioning with copper-chelating antioxidant and uv-absorbing activity from imidazole ring.

Why It's Used: Antioxidant nmf amino acid — histidine's imidazole ring provides unique copper-chelating antioxidant activity alongside nmf hydration and uv absorption not available from other nmf amino acids.

How It Works: Imidazole ring chelates cu²⁺ and fe²⁺ for antioxidant metal chelation (inhibiting fenton reaction). uv absorption at 211nm provides partial photoprotection. precursor for carnosine (with beta-alanine) for anti-glycation. nmf component via imidazole + carboxylate water binding.

Typically Found In: Antioxidant skincare,anti-aging products,nmf moisturisers

TECHNICAL DETAILS

Primary Category: Active ingredient – imidazole amino acid

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%–5%

SOURCING & ETHICS

Vegan Status: Yes – fermentation

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

Histidine's imidazole ring's copper chelation provides the same chemical mechanism as the pharmaceutical cuprimine (d-penicillamine) used for copper chelation therapy in wilson's disease — just with significantly lower affinity. the imidazole copper chelation prevents fenton-type radical generation from free copper ions that would otherwise catalyse hydroxyl radical production from hydrogen peroxide.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12