Neutrogena® Hydro Boost Ultra Hydrating Serum With Hyaluronic Acid

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: 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: Provides humectant hydration and active ingredient solubilization with excellent skin feel.

Why It's Used: Preferred glycol humectant in premium and k-beauty formulations for superior skin feel vs propylene glycol with equivalent functionality.

How It Works: Two hydroxyl groups at 1,3-positions provide water binding and solvent activity. better tolerated than propylene glycol with minimal sensitization risk. 4-carbon backbone provides slightly greater hydrophobic character enabling dissolution of less polar actives vs pg.

Typically Found In: Toners,essences,serums,k-beauty formulas

TECHNICAL DETAILS

Primary Category: Functional ingredient – glycol 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%–10%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

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

K-beauty's preference for butylene glycol over propylene glycol is driven by two factors: bg's superior skin feel (less tacky than pg's higher viscosity) and its lower sensitization potential (1,3-bg has better spatial distribution of hydroxyl groups that reduces protein interaction vs pg's 1,2-position oh groups).

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides silicone-characteristic silky feel and skin protection with adjustable viscosity.

Why It's Used: The benchmark cosmetic silicone – sets the gold standard for silky application feel, spreadability, and skin protection in virtually all skin care categories.

How It Works: Polydimethylsiloxane chain flexibility provides extremely low surface tension and high spreadability. inert si-o backbone provides chemical stability and excellent skin tolerance. occlusive film formation reduces tewl. higher viscosity grades provide more intense conditioning.

Typically Found In: Moisturizers,foundations,primers,sunscreens – nearly universal

TECHNICAL DETAILS

Primary Category: Functional ingredient – polydimethylsiloxane

Secondary Functions: Barrier sealing,softening

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–30%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

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

Dimethicone's exceptional silky feel arises from its very low intermolecular attractive forces (weak van der waals forces due to non-polar methyl groups) that allow silicone chains to slide freely over skin. the coefficient of kinetic friction for pdms against skin (~0.04) is among the lowest of any cosmetic material – explaining why even small amounts transform product feel.

Last Verified: Cosing database,cir safety assessment

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: 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

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

Last Verified: Cosing database,neopentyl glycol diheptanoate technical literature

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides moisture retention as a key nmf component and supports barrier phospholipid synthesis.

Why It's Used: Core nmf amino acid humectant in skin conditioning formulations.

How It Works: Hydroxyl group binds water for humectant activity. phosphoserine forms phospholipid head groups for barrier membrane synthesis. nmf component contributing to stratum corneum natural moisture retention.

Typically Found In: Nmf moisturizers,skin conditioning products

TECHNICAL DETAILS

Primary Category: Active ingredient – amino acid

Secondary Functions: Nmf component,barrier phospholipid support

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

Serine is among the highest-concentration amino acids in the stratum corneum nmf (approximately 4% of total nmf dry weight), making it a physiologically relevant humectant ingredient for barrier-mimetic formulations.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides hyaluronic acid hydration in the most formulation-stable and compatible form.

Why It's Used: The standard form of ha used in cosmetics – more stable than free ha, better solubility, and equivalent skin hydration benefits.

How It Works: Sodium salt reduces the polyelectrolyte repulsion of ha chains, allowing better packing in formulations. on skin, sodium ions dissociate and the ha chain unfolds to its full water-binding conformation. provides full ha humectant and barrier benefits equivalent to free ha.

Typically Found In: Hydrating serums,toners,moisturizers,sheet masks,anti-aging products

TECHNICAL DETAILS

Primary Category: Active ingredient – ha sodium salt

Secondary Functions: Equivalent ha hydration,superior stability

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 – bacterial 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

The sodium salt form of ha has approximately 10% better water solubility than free hyaluronic acid at equivalent molecular weight due to reduced chain-chain electrostatic repulsion from partial sodium counterion screening. this improved solubility enables higher concentration formulations without viscosity issues.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides nmf conditioning with sphingolipid precursor activity for barrier ceramide support.

Why It's Used: Barrier-supporting nmf amino acid — threonine's role as a serine and sphingolipid precursor provides unique barrier lipid biosynthesis support beyond simple nmf moisture retention.

How It Works: Beta-hydroxyl group provides humectant water binding as nmf component. converted to serine and glycine for collagen and barrier protein synthesis. serine is precursor for sphingolipid (ceramide) synthesis via serine palmitoyltransferase — the rate-limiting step in ceramide de novo synthesis.

Typically Found In: Barrier repair products,nmf moisturisers

TECHNICAL DETAILS

Primary Category: Active ingredient – serine family 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

Threonine's indirect ceramide synthesis support via serine→sphingolipid pathway provides a metabolic rationale for including threonine in barrier repair formulations: by providing the serine precursor substrate for serine palmitoyltransferase (spt — the rate-limiting ceramide synthesis enzyme), threonine may support endogenous ceramide production in barrier-compromised skin where spt substrate availability may be limiting.

Last Verified: Cosing database,cir safety assessment

Primary Sources: 2026-03-12