Beauty ingredient research

Beauty ingredients explained in plain English

Browse the review database to understand what an ingredient is, what it does in a beauty formula, when it is useful, and when it deserves caution across skincare, haircare, bodycare, makeup, and more.

20769

Reviewed ingredients

524

Low-concern standouts

2884

Need usage caution

Showing 60 of 1,094
AllUV absorberUV filterabrasiveabsorbentacne treatmentactiveactive ingredientadhesivealkalizing agentamino acidanti-aginganti-androgenanti-cavityanti-cavity agentanti-inflammatoryanti-irritantanticariesanticavity agentantidandruffantifungalantimicrobialantioxidantantiperspirantantiplaqueastringentbarrier repairbarrier supportbarrier-repairbarrier-supportbinderbinding agentbiotechbiotechnologybond-builderbotanicalbotanical extractbotanical oilbotanical waterbrighteningbrightening agentbufferbuffering agentcell-communicating ingredientceramidechelating agentchemicalchemical intermediateclaycleansercleansingcleansing agentcolorantconditionerconditioningconditioning agentcooling agentcosmeticcosmetic additivecosmetic colorantcosmetic ingredientcosmetic pigmentcosmetic powdercosmetic-texturizercosmetic-waxcosmeticscrosslinking agentdelivery agentdelivery systemdenaturantdeodorantdeodorant agentdepigmenting agentdepilatorydepilatory agentdesensitizing agentdyedye intermediatedye precursordye-intermediateemollientemulsifierenzymeessential oilexfoliantexperimentaleyelashfermentfilm formerfilm-formerfilm-formingfilm-forming agentfirming agentfixativeflavoring agentformulationfragrancefragrance ingredientfunctional ingredientgashair carehair colorhair coloranthair conditionerhair dyehair removalhair-carehair-colorhaircarehumectantindustrialinsecticideintermediatelashlash carelash enhancerlash-and-browlip carelipidmakeupmarine extractmasking agentmicrobiomemicrobiome modulatormineralmoisturizernail carenail-careocclusiveoilopacifieropacifying agentoptical agentoral careotheroxidative dyeoxidative dye precursoroxidizing agentpH adjusterpain reliefpenetration enhancerpeptidepersonal careph adjusterpharmaceuticalpheromonepigmentplant oilplasticizerpolymerpolymer precursorprebioticprescription-drugpreservativepreservative boosterprobioticprocessing agentprocessing aidpropellantproteinpurifyingreducing agentretinoidscalp caresebum regulatorsebum-regulatorself-tannerself-tanningsensory additivesensory agentsensory modifiersiliconeskin barrierskin barrier supportskin conditionerskin conditioningskin conditioning agentskin lighteningskin protectantskin-conditioningskin-conditioning agentskin-identicalskin-identical ingredientskin-lighteningskin-lightening agentskincaresolventsoothingsoothing agentstabilizerstimulantsunscreensurfactantsyntheticsynthetic colorantsynthetic dyesynthetic resinsynthetic-coloranttexture enhancertexturizerthickenertoneruv-absorberuv-filtervasoactivevasodilatorviscosity controlviscosity controllingviscosity controlling agentvitaminwax

Humectant

Butylene Glycol

Butylene Glycol

4.2

A widely used, low-irritation humectant that helps products feel smooth and hydrating without being sticky.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

Butylglycerin

Butylglycerin

4.0

Butylglycerin is a gentle, synthetic humectant that pulls moisture into the skin and improves product feel without common irritation.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Skin conditioning agent

Butyric Acid

Butyric Acid

3.8

Butyric acid is an emerging skincare ingredient that may support a healthy skin microbiome, but research is still early and it can be irritating at higher concentrations.

Irritation

moderate

Source

natural

beautyskincarehumectant
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Humectant

Cacao Seed Water

THEOBROMA CACAO SEED WATER

4.0

A gentle, antioxidant-rich water from cacao seeds that hydrates and soothes skin without the heaviness of cocoa butter.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Calcium Aspartate

CALCIUM ASPARTATE

3.8

Calcium Aspartate is a gentle mineral-amino acid ingredient that may help support skin hydration and barrier function, but research is still early.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

Calcium Fructoheptonate

Calcium Fructoheptonate

3.8

A gentle humectant and mild exfoliant that hydrates without irritation, but research is still limited.

Irritation

low

Source

semi-synthetic

beautyskincarehumectant
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Humectant

Calcium Glycinate

Calcium Glycinate

4.0

A gentle, hydrating mineral that helps calm the skin and support its natural barrier without irritation.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

Calcium Lactate

Calcium Lactate

4.0

Calcium lactate is a gentle, hydrating exfoliant that helps smooth skin without the sting of stronger acids.

Irritation

low

Source

synthetic

beautyskincarehumectantexfoliant
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Humectant

Calcium Pantothenate

Calcium Pantothenate

4.0

A stable, water-soluble form of Vitamin B5 that helps hydrate and soothe the skin without irritation.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

Calcium Polygamma-Glutamate

CALCIUM POLY-GAMMA-GLUTAMATE

4.0

A gentle, plant-based humectant that holds water on the skin's surface, offering a smoother feel and lasting hydration without stickiness.

Irritation

low

Source

biotech

beautyskincarehumectant
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Humectant

Calcium Polyglutamate Crosspolymer

Calcium Polyglutamate Crosspolymer

4.0

A next-generation humectant that forms a flexible, breathable film to lock in moisture without the stickiness of traditional hyaluronic acid.

Irritation

low

Source

biotech

beautyskincarehumectantfilm former
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Humectant

Calf Skin Extract

Calf Skin Extract

2.5

Calf Skin Extract is a protein-rich ingredient that may help moisturize and temporarily smooth skin, but it lacks strong research and raises ethical and sourcing concerns.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Calliblepharis Ciliata Extract

Calliblepharis Ciliata Extract

3.5

A gentle red seaweed extract that helps hydrate skin and may offer antioxidant protection, but research is still early.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Camellia Japonica Seed Water

CAMELLIA JAPONICA SEED WATER

4.0

A gentle, hydrating water that provides antioxidant benefits and helps soothe the skin, making it a great base for sensitive skin formulas.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Camellia Seed Ferment Filtrate

SACCHAROMYCES/CAMELLIA JAPONICA SEED OIL/GLYCERIN FERMENT FILTRATE

4.0

A gentle, fermented ingredient that provides hydration and supports a healthy-looking skin barrier, though research is still emerging.

Irritation

low

Source

biotech

beautyskincarehumectantskin-conditioning agent
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Humectant

Camphanediol

Camphanediol

3.8

Camphanediol is a synthetic humectant that helps hydrate the skin and improve product feel, with low irritation potential but limited research.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

Cantaloupe Fruit Extract

Cucumis Melo Inodorus Fruit Extract

3.8

A gentle, water-loving fruit extract that helps hydrate skin and provides a modest dose of antioxidants, but its benefits are mild compared to more concentrated active ingredients.

Irritation

low

Source

natural

beautyskincarehumectantantioxidant
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Humectant

Caprylyl Glycol

Caprylyl Glycol

4.5

A mild, multifunctional ingredient that hydrates skin and helps preserve formulas without the irritation of traditional preservatives.

Irritation

low

Source

synthetic

beautyskincarehumectantpreservative booster
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Humectant

Carbocysteine

CARBOCYSTEINE

3.5

Carbocysteine is a gentle, hydrating amino acid derivative that may help support skin barrier health, but research in topical cosmetics is still limited.

Irritation

low

Source

synthetic

beautyskincarehumectant
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Humectant

Carboxymethyl Chitosan

Carboxymethyl Chitosan

4.0

A gentle, water-soluble chitosan derivative that hydrates and forms a protective film on skin, with some soothing and antioxidant potential.

Irritation

low

Source

semi-synthetic

beautyskincarehumectantfilm-former
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Humectant

Carboxymethyl Chitosan Succinamide

CARBOXYMETHYL CHITOSAN SUCCINAMIDE

4.0

A gentle, water-loving derivative of chitosan that helps hydrate and form a protective film on the skin, with early research suggesting soothing benefits.

Irritation

low

Source

semi-synthetic

beautyskincarehumectantfilm-former
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Film Former

Carboxymethyl Levan

Carboxymethyl Levan

4.0

A gentle, biotech-derived film former that helps lock in moisture and may soothe the skin without clogging pores.

Irritation

low

Source

biotech

beautyskincarefilm-formerhumectant
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Humectant

Carnitine PCA

CARNITINE PCA

4.0

A gentle, water-loving ingredient that pulls moisture into the skin and helps maintain a healthy barrier.

Irritation

low

Source

semi-synthetic

beautyskincarehumectant
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Humectant

Carpopeltis Affinis Extract

CARPOPELTIS AFFINIS EXTRACT

4.0

A gentle red algae extract that helps hydrate and soothe the skin, with emerging research on its antioxidant potential.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Carrot Root Juice

Daucus Carota Sativa Root Juice

4.0

Carrot Root Juice is a gentle, water-based ingredient that hydrates and provides antioxidant benefits, but its effects are mild compared to concentrated extracts or oils.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Carrot Root Water

Daucus Carota Sativa Root Water

4.0

A gentle, antioxidant-rich water from carrots that hydrates and soothes skin without irritation.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Cassia Seed Polysaccharide

Cassia Angustifolia Seed Polysaccharide

4.0

A gentle, plant-based polysaccharide that helps hydrate and form a protective film on the skin, making it a good option for sensitive or dry skin types.

Irritation

low

Source

natural

beautyskincarehumectantfilm former
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Humectant

Cellobiose Octanonanoate

Cellobiose Octanonanoate

4.0

A gentle, sugar-based humectant that helps hydrate skin without stickiness, though research is still emerging.

Irritation

low

Source

semi-synthetic

beautyskincarehumectant
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Humectant

Ceramium Kondoi Extract

Ceramium Kondoi Extract

3.8

A gentle red algae extract that helps hydrate and calm the skin, but research on its specific benefits is still limited.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Cereus Hildmannianus Extract

Cereus Hildmannianus Extract

4.0

A gentle, plant-based humectant that helps hydrate and soothe the skin, with antioxidant benefits to protect against environmental stress.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Cetyl PCA

Cetyl PCA

4.3

Cetyl PCA is a gentle humectant that pulls moisture into the skin and leaves it feeling smooth without greasiness.

Irritation

low

Source

semi-synthetic

beautyskincarehumectantemollient
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Humectant

Channeled Wrack Extract

Pelvetia Canaliculata Extract

4.0

A gentle seaweed extract that helps hydrate and protect the skin with antioxidants, suitable for most skin types.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Cherry Fruit Water

Prunus Avium Fruit Water

3.8

A gentle, hydrating base ingredient from cherries that offers mild antioxidant benefits and a subtle fruity scent, but lacks strong clinical evidence for dramatic skin changes.

Irritation

low

Source

natural

beautyskincarehumectant
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Exfoliant

Chia Seed Powder

Salvia Hispanica Seed Powder

4.0

Chia seed powder offers gentle physical exfoliation and a boost of hydration, making it a mild choice for most skin types.

Irritation

low

Source

natural

beautyskincareexfolianthumectant
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Film Former

Chitosan

Chitosan

4.0

Chitosan is a gentle, natural film-former that helps lock in moisture and can provide a light, protective barrier on skin or hair.

Irritation

low

Source

natural

beautyskincarefilm-formerhumectant
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Antioxidant

Chitosan Glutathionamide

Chitosan Glutathionamide

3.8

A novel hybrid ingredient that pairs chitosan's film-forming and hydrating properties with glutathione's antioxidant potential, though research on this specific conjugate is still limited.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidanthumectant
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Humectant

Chlorella and Lupin Ferment

CHLORELLA VULGARIS/LUPINUS ALBUS PROTEIN FERMENT

4.0

A gentle fermented ingredient that may help hydrate and soothe skin, though research is still limited.

Irritation

low

Source

biotech

beautyskincarehumectant
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Humectant

Citrulline

CITRULLINE

4.0

Citrulline is a gentle, hydrating amino acid that helps maintain skin moisture and supports a healthy skin barrier.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Citrus Keraji Fruit Water

Citrus Keraji Fruit Water

3.8

A gentle, antioxidant-rich fruit water that hydrates and refreshes without heavy oils, but its benefits are based more on tradition than robust clinical studies.

Irritation

low

Source

natural

beautyskincarehumectantantioxidant
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Humectant

Cladosiphon Polysaccharide

CLADOSIPHON NOVAE-CALEDONIAE POLYSACCHARIDE

4.0

A gentle, hydrating seaweed-derived ingredient that helps soothe skin and lock in moisture without clogging pores.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Cobetia Marina Glycosaminoglycans

Cobetia Marina Glycosaminoglycans

4.0

A biotech marine ingredient that mimics the skin's natural moisture-holding molecules, offering gentle hydration and a plumping effect.

Irritation

low

Source

biotech

beautyskincarehumectant
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Humectant

Coconut Flower Nectar Ferment

Saccharomyces/Coconut Flower Nectar Ferment Filtrate

4.0

A gentle fermented ingredient that helps hydrate and support the skin barrier, ideal for sensitive and dry skin types.

Irritation

low

Source

biotech

beautyskincarehumectant
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Humectant

Coconut Flower Sugar

Cocos Nucifera Flower Sugar

4.0

A gentle, natural humectant that helps skin retain moisture, but research on its cosmetic benefits is still limited.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Coconut Fruit Extract

Cocos Nucifera Fruit/Fruit Juice Extract

4.0

A gentle, hydrating extract from coconut fruit that helps soften and soothe skin without the heavy feel of coconut oil.

Irritation

low

Source

natural

beautyskincarehumectantemollient
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Humectant

Coconut Fruit Juice

COCOS NUCIFERA FRUIT JUICE

4.0

Coconut fruit juice is a gentle, hydrating ingredient that provides light moisture and soothing benefits, ideal for most skin types.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Codium Tomentosum Powder

Codium Tomentosum Powder

3.8

A gentle seaweed powder that helps hydrate and soothe the skin, but research on its benefits is still limited.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Collagen

Collagen

3.8

Collagen is a popular moisturizing ingredient that helps skin feel plump and hydrated, but it cannot directly replace lost collagen in the skin.

Irritation

low

Source

natural

beautyskincarehumectant
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