Paula's Choice Boost 10% Niacinamide Booster

DESCRIPTION

What It Does: Soothes irritation, accelerates wound healing, promotes skin cell renewal, and provides mild keratolytic exfoliation.

Why It's Used: Gold standard multi-function soothing active – one of the most widely used cosmetic ingredients across all product types for its exceptional tolerability and clinically proven multi-action skin conditioning.

How It Works: Promotes keratinocyte proliferation and fibroblast migration for wound healing. mild keratolytic activity by disrupting corneocyte binding. anti-irritant via direct protein binding and anti-inflammatory cytokine reduction. humectant activity via hydroxyl groups.

Typically Found In: Post-procedure products,sensitive skin formulas,wound care,anti-acne treatments,baby products

TECHNICAL DETAILS

Primary Category: Active ingredient – soothing / anti-inflammatory

Secondary Functions: Wound healing,keratolytic,anti-irritant

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 or comfrey-derived

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: Exceptionally well-tolerated; suitable for all skin types including baby and compromised skin.

Safe for Sensitive Skin: Yes – particularly recommended for sensitive skin

SAFETY & COMPATIBILITY

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

Works Well With: Ceramides,panthenol,allantoin,hyaluronic acid,centella asiatica

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Allantoin's keratinocyte proliferation stimulation occurs via receptor-mediated signaling (possibly machr activation) rather than non-specific irritation-driven proliferation, making it a true wound-healing stimulant rather than a pro-inflammatory proliferative signal.

Last Verified: Cosing database,cir safety assessment,araújo et al. allantoin review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Reduces inflammation, deeply hydrates, stimulates collagen synthesis, accelerates wound healing.

Why It's Used: Used in anti-aging, sensitive skin, post-procedure, and eczema care for multi-action anti-inflammatory, moisturizing, and regenerative benefits.

How It Works: Binds to dectin-1 and cr3 receptors on macrophages and keratinocytes activating tgf-beta and collagen synthesis pathways. also activates macrophage phagocytosis for wound healing. humectant from polysaccharide hydroxyl groups.

Typically Found In: Anti-aging serums,sensitive skin products,post-procedure care,eczema treatments

TECHNICAL DETAILS

Primary Category: Active ingredient – polysaccharide / immunomodulator

Secondary Functions: Immunomodulator,wound healing,collagen stimulation

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: Yes – yeast or oat-derived

Halal Status: Yes

Source Notes: Derived from saccharomyces cerevisiae yeast (1,3/1,6-linked) or avena sativa oats (1,3/1,4-linked). molecular weight affects penetration – lower mw for skin penetration vs high mw for surface hydration.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; ideal for reactive and sensitive skin.

Safe for Sensitive Skin: Yes – particularly recommended for sensitive skin

SAFETY & COMPATIBILITY

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

Works Well With: Ceramides,panthenol,allantoin,hyaluronic acid,centella asiatica

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Yeast beta-1,3/1,6-glucan receptor binding to dectin-1 on keratinocytes activates tgf-beta1, the key pro-collagen cytokine, stimulating fibroblast collagen production. this makes beta-glucan one of the few non-retinoid, non-peptide ingredients with direct receptor-mediated collagen stimulation.

Last Verified: Cosing database,wasser (2002) beta-glucan review,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides anti-glycation and anti-carbonylation activity protecting collagen from glycation-induced crosslinking.

Why It's Used: Natural anti-age dipeptide targeting glycation — complementary to antioxidant-only anti-aging strategies with documented collagen protection.

How It Works: Histidine imidazole chelates cu²⁺ for antioxidant metal chelation. beta-alanine traps reactive carbonyl species (glycating aldehydes). quenches 4-hydroxynonenal (hne) protein carbonylation. anti-glycation via competing with lysine residues.

Typically Found In: Anti-aging serums,anti-glycation products,longevity skincare

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: 0.5%–5%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

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

Carnosine's anti-glycation mechanism is sacrificial carbonyl trapping: reactive carbonyl species (methylglyoxal, glyoxal) that would normally glycate collagen lysines are instead captured by carnosine's free amino groups — carnosine acts as a sacrificial protector for collagen, being consumed in the process of preventing more damaging collagen glycation.

Last Verified: Cosing database,guiotto et al. carnosine anti-glycation review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides antimicrobial skin conditioning with deodorant activity and preservation system enhancement.

Why It's Used: Multifunctional clean beauty preservation active — ethylhexylglycerin provides antimicrobial, deodorant, and skin conditioning in a single ingredient accepted in most natural cosmetic certification schemes.

How It Works: Glycerol ether provides antimicrobial via bacterial membrane phospholipid disruption. deodorant activity via reduction of underarm lipase enzyme activity (similar mechanism to triethyl citrate). skin conditioning from glycerol humectant component. synergistic with phenoxyethanol and diols.

Typically Found In: Natural preservation systems,deodorants,skin conditioning products

TECHNICAL DETAILS

Primary Category: Functional ingredient – antimicrobial glycerol ether

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%–0.5%

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

Ethylhexylglycerin's deodorant mechanism is pharmacologically identical to triethyl citrate: both inhibit skin surface microbial lipase enzymes that convert odourless triglycerides to odorous free fatty acids. the glycerol ether structure of ethylhexylglycerin, combined with the 2-ethylhexyl chain, provides lipase inhibition similar to ester-based lipase inhibitors from a different chemical class.

Last Verified: Cosing database,schülke sensiva sc 10 technical data,cir safety assessment

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Stimulates collagen i synthesis through erβ nuclear receptor activation, improves post-menopausal skin thickness and elasticity, provides antioxidant protection, and mildly inhibits 5-α-reductase for sebum regulation.

Why It's Used: Provides hormone-pathway collagen stimulation through phytoestrogen chemistry — a mechanistically distinct anti-aging route from peptide/growth factor approaches, particularly relevant for post-menopausal skin where declining estrogen directly reduces skin collagen content.

How It Works: Isoflavone binds erβ (k_d ~1–10 nm, ~100× lower affinity than 17β-estradiol) → erβ dimerisation → ere-responsive gene activation in fibroblasts. col1a1, hyaluronan synthase, and vegf genes are erβ-responsive, providing collagen, ha, and vascularisation upregulation.

Typically Found In: Anti-aging,post-menopausal skin care

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%–1%

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

Skin erβ expression is 30–40× higher than erα — phytoestrogens preferentially activate erβ (minimal erα activity) providing skin-specific estrogenic benefit without systemic estrogenic risk from erα activation.

Last Verified: Cosing database,isoflavone phytoestrogen skin erβ 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: Panthenol deeply moisturizes skin and hair, soothes irritation, accelerates wound healing, strengthens the skin barrier, and improves hair elasticity and shine.

Why It's Used: It is used because it is exceptionally versatile, working in both skin and hair formulations. it is gentle enough for sensitive and post-procedure skin, and converts to the active vitamin b5 within the skin.

How It Works: Panthenol penetrates skin and hair, where it is oxidized to pantothenic acid (vitamin b5), a coenzyme a precursor essential to metabolism. in skin, it acts as a humectant and stimulates fibroblast proliferation. in hair, it coats the shaft, improving manageability.

Typically Found In: Moisturizers,serums,toners,after-sun products,wound healing products,shampoos,conditioners,hair masks,beard care

TECHNICAL DETAILS

Primary Category: Active ingredient – provitamin b5

Secondary Functions: Anti-inflammatory,wound healing,hair conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–5% (typical: 1–3%)

SOURCING & ETHICS

Vegan Status: Yes – synthetically produced

Halal Status: Yes

Source Notes: Commercially synthesized. both d- and dl-forms used in cosmetics; d-panthenol is the biologically active isomer but dl-panthenol is less expensive and widely used.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low; one of the most soothing ingredients in cosmetics

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Extremely rare contact allergy; considered one of the safest cosmetic ingredients. suitable for all skin types.

Safe for Sensitive Skin: Yes – ideal for sensitive, reactive, and post-procedure skin

SAFETY & COMPATIBILITY

Safety Profile: Exceptionally safe. ewg hazard score: 1. no significant concerns for irritation, sensitization, or systemic toxicity. safe during pregnancy.

Works Well With: Hyaluronic acid,ceramides,allantoin,niacinamide,centella asiatica,retinol (reduces irritation),glycerin

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Panthenol has demonstrated wound-healing properties in clinical studies, stimulating fibroblast proliferation and migration. its dual humectant and anti-inflammatory action makes it particularly effective in barrier-repair formulations.

Last Verified: Cosing database,cir safety assessment,ebner et al. (2002) skin pharmacology and applied skin physiology

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

DESCRIPTION

What It Does: Stabilises o/w and w/o emulsions through biomimetic phospholipid bilayer formation, supplements sc barrier lipids for barrier repair, and forms liposomes and lamellar delivery vehicles for encapsulated active delivery.

Why It's Used: Phospholipids are uniquely bifunctional: they provide conventional emulsification and form genuine liposomal bilayer vesicles for encapsulated active delivery — a dual function unavailable from synthetic emulsifiers.

How It Works: The phosphocholine head group provides strong h-bonding hydrophilicity while the dual fatty acid tails provide lipophilic anchoring — this wedge-shaped geometry spontaneously forms closed bilayer vesicles (liposomes) that encapsulate actives for sustained release and enhanced sc penetration.

Typically Found In: Emulsions,liposomal delivery,barrier repair

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%–15%

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

Phospholipid's wedge-shaped geometry (large head relative to two acyl tails) preferentially forms spherical bilayer vesicles (liposomes) rather than flat lamellar phases — this curvature preference enables self-assembly of drug delivery liposomes simply by hydration of the phospholipid film.

Last Verified: Cosing database,lecithin phospholipid liposomal delivery review

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Replenishes age-declining coq10 for mitochondrial energy support and membrane antioxidant protection.

Why It's Used: The mitochondrial anti-aging ingredient — coq10 skin levels decrease ~50% from age 20 to 80 and topical supplementation directly addresses this documented decline.

How It Works: Ubiquinone/ubiquinol redox cycle carries electrons in mitochondrial complexes i–iii for atp production. reduced ubiquinol quenches lipid peroxyl radicals in inner mitochondrial membrane. coq10 depletion in aging skin reduces atp production and membrane antioxidant defence simultaneously.

Typically Found In: Anti-aging serums,mitochondrial skincare,antioxidant 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: 0.01%–1%

SOURCING & ETHICS

Vegan Status: Yes – from fermentation or synthetic

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

Coq10's mitochondrial role places it at the nexus of aging biology — a 50% decline from age 20 to 80 is mechanistically linked to reduced atp production, increased mitochondrial superoxide leak, and mtdna damage constituting the 'mitochondrial theory of aging' at the cellular level.

Last Verified: Cosing database,shindo et al. coq10 skin aging study

Primary Sources: 2026-03-12