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 20,769
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

Fragrance Ingredient

Ethylphenyl Dimethylpropanal

3-(O-ETHYLPHENYL)-2,2-DIMETHYLPROPIONALDEHYDE

3.5

A synthetic floral scent ingredient that is generally safe at low levels but may cause allergic reactions in sensitive individuals.

Irritation

low

Source

synthetic

beautyskincarefragrance
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Fragrance

Ethylphenylbutyraldehyde

AR-ETHYLPHENYLBUTYRALDEHYDE

3.5

A synthetic fragrance aldehyde that adds a pleasant floral note but may cause skin sensitivity in some people.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Film Former

Ethyltosylamide Epoxy Resin-2

ETHYLTOSYLAMIDE EPOXY RESIN-2

3.0

A synthetic resin that helps nail polish stick better and last longer, but it's not a moisturizer or active skincare ingredient.

Irritation

low

Source

synthetic

beautynail carefilm former
Read ingredient review

Fragrance Ingredient

Ethyltrimethylcyclopenten Acetate

ETHYLTRIMETHYL-3-CYCLOPENTEN-1-ACETATE

3.5

A synthetic scent ingredient that adds a pleasant aroma but offers no skincare benefits and may cause sensitivity in some people.

Irritation

low

Source

synthetic

beautyskincarefragrance
Read ingredient review

Chelating Agent

Etidronic Acid

Etidronic Acid

4.0

A gentle chelating agent that helps preserve formula stability and effectiveness by neutralizing problematic metal ions.

Irritation

low

Source

synthetic

beautyskincarechelating agent
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UV Filter

Etocrylene

Etocrylene

3.5

Etocrylene is a synthetic UV filter that helps protect skin from sun damage, but it is less common in modern formulations due to concerns about photostability and potential skin sensitivity.

Irritation

low

Source

synthetic

beautyskincaresunscreen
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Fragrance

Eucalyptol

EUCALYPTOL

3.8

Eucalyptol adds a refreshing, cooling feel to products but can be irritating for sensitive skin, especially at higher concentrations.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Soothing agent

Eucalyptus Alba Leaf Extract

Eucalyptus Alba Leaf Extract

3.8

A gentle botanical extract that may help calm skin and fight free radicals, but research is limited compared to more common eucalyptus species.

Irritation

low

Source

natural

beautyskincarebotanical extract
Read ingredient review

Fragrance

Eucalyptus Cinerea Leaf Oil

EUCALYPTUS CINEREA LEAF OIL

3.5

A fragrant essential oil that can add a refreshing scent to products, but may cause irritation for sensitive skin types.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Fragrance

Eucalyptus Cinerea Leaf Water

EUCALYPTUS CINEREA LEAF WATER

3.8

A gentle, aromatic water that may offer mild soothing and refreshing benefits, but its effects are largely due to its pleasant scent and water content.

Irritation

low

Source

natural

beautyskincaresoothing agent
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Fragrance component

Eucalyptus Dives Leaf Extract

EUCALYPTUS DIVES LEAF EXTRACT

3.8

A botanical extract with a fresh, minty scent that may help clarify oily or blemish-prone skin, but can be irritating for sensitive types.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
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Fragrance

Eucalyptus Dives Leaf Oil

EUCALYPTUS DIVES LEAF OIL

3.5

Eucalyptus Dives Leaf Oil adds a fresh, herbal scent and may help with acne-prone skin, but it can be irritating for sensitive skin types.

Irritation

moderate

Source

natural

beautyskincareessential oil
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Fragrance

Eucalyptus Dives Oil

EUCALYPTUS DIVES LEAF/TWIG OIL

3.5

Eucalyptus Dives Oil adds a fresh, herbal scent and may help with mild antimicrobial effects, but it can be irritating for sensitive skin.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Antioxidant

Eucalyptus Dunnii Leaf Extract

EUCALYPTUS DUNNII LEAF EXTRACT

3.8

A gentle botanical extract with antioxidant potential, but research on its specific benefits in skincare is still limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antimicrobial

Eucalyptus Leaf Extract

Eucalyptus Globulus Leaf Extract

3.8

Eucalyptus leaf extract can help calm acne and refresh skin, but its potent essential oil components may irritate sensitive skin.

Irritation

moderate

Source

natural

beautyskincareantioxidant
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Fragrance

Eucalyptus Leaf Oil

Eucalyptus Species Leaf Oil

3.8

Eucalyptus leaf oil adds a refreshing scent and may offer mild soothing effects, but it can be irritating for sensitive skin.

Irritation

moderate

Source

natural

beautyskincarefragrance
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Exfoliant

Eucalyptus Leaf Powder

EUCALYPTUS GLOBULUS LEAF POWDER

3.5

A natural exfoliant with a strong herbal scent, but may irritate sensitive skin due to its essential oil content.

Irritation

moderate

Source

natural

beautyskincareexfoliant
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Soothing agent

Eucalyptus Leaf Water

EUCALYPTUS PARVULA LEAF WATER

3.8

A gentle, aromatic water that adds a refreshing feel and subtle soothing benefits, but research on this specific species is limited.

Irritation

low

Source

natural

beautyskincaresoothing
Read ingredient review

Fragrance

Eucalyptus Oil

EUCALYPTUS GLOBULUS LEAF/TWIG OIL

3.8

Eucalyptus oil adds a fresh, invigorating scent and may help with oily or blemish-prone skin, but it can be irritating for sensitive skin types.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Fragrance

Eucalyptus Parvula Leaf Oil

EUCALYPTUS PARVULA LEAF OIL

3.8

A fragrant eucalyptus oil that adds a fresh scent and may offer mild soothing effects, but can be irritating for sensitive skin.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Fragrance component

Eucalyptus Pulverulenta Leaf Water

EUCALYPTUS PULVERULENTA LEAF WATER

3.8

A gentle, aromatic leaf water that adds a subtle eucalyptus scent and mild soothing feel, but lacks strong clinical backing for skin benefits.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
Read ingredient review

Skin conditioning agent

Eucalyptus Radiata Extract

EUCALYPTUS RADIATA FLOWER/LEAF/STEM EXTRACT

4.0

Eucalyptus radiata extract offers a refreshing, purifying boost for oily or congested skin, but its natural essential oil content can be irritating for sensitive skin.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
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Fragrance

Eucalyptus Radiata Oil

EUCALYPTUS RADIATA LEAF/STEM OIL

3.8

Eucalyptus radiata oil adds a fresh, herbal scent and may help clarify oily or blemish-prone skin, but it can be irritating for sensitive skin and should always be used in low concentrations.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Soothing agent

Eucalyptus Smithii Leaf Extract

Eucalyptus Smithii Leaf Extract

3.8

A plant extract with antimicrobial and soothing potential, but may irritate sensitive skin due to its essential oil content.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
Read ingredient review

Fragrance

Eucalyptus Smithii Leaf Oil

EUCALYPTUS SMITHII LEAF OIL

3.8

A fragrant essential oil with mild antimicrobial and soothing properties, but can be irritating for sensitive skin if used at high concentrations.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Humectant

Eucheuma Serra Extract

Eucheuma Serra Extract

4.0

A gentle seaweed extract that helps hydrate and soothe skin while forming a light protective layer.

Irritation

low

Source

natural

beautyskincarehumectant
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Humectant

Eucheuma Spinosum Extract

Eucheuma Spinosum Extract

4.0

A gentle, hydrating seaweed extract that helps skin retain moisture and feel smooth, with low irritation risk.

Irritation

low

Source

natural

beautyskincarehumectant
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Antioxidant

Eucommia Pericarp Extract

Eucommia Ulmoides Pericarp Extract

3.8

A gentle plant extract with antioxidant potential, but human skin research is still limited.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Eugenia Operculata Leaf Powder

EUGENIA OPERCULATA LEAF POWDER

3.5

A gentle botanical powder with antioxidant potential, but research on its specific skincare benefits is still limited.

Irritation

low

Source

natural

beautyskincarebotanical
Read ingredient review

Fragrance

Eugenol

EUGENOL

3.5

Eugenol is a natural fragrance ingredient that can cause irritation for sensitive skin, so it's best used in low concentrations.

Irritation

moderate

Source

natural

beautyskincarefragrance
Read ingredient review

Fragrance Ingredient

Eugenyl Formate

Eugenyl Formate

3.5

Eugenyl formate is a synthetic fragrance ingredient that adds a clove-like scent but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Antioxidant

Eugenyl Glucoside

Eugenyl Glucoside

4.0

Eugenyl Glucoside is a gentle, water-soluble antioxidant that helps protect skin from environmental stress while being far less irritating than its parent compound, eugenol.

Irritation

low

Source

semi-synthetic

beautyskincareantioxidant
Read ingredient review

Fragrance Ingredient

Eugenyl Phenylacetate

EUGENYL PHENYLACETATE

3.5

Eugenyl phenylacetate is a synthetic fragrance ingredient that adds a clove-like scent but may cause skin irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarefragrance
Read ingredient review

Antioxidant

Euglena Ferment

EUGLENA/OLEIC ACID FERMENT

3.8

A gentle, antioxidant-rich ferment from microalgae that may help protect skin from environmental stress, though research is still early.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Antioxidant

Euonymus Bark Extract

EUONYMUS SACHALINENSIS BARK EXTRACT

3.5

A gentle botanical extract with antioxidant potential, but research is limited and benefits are not yet well-established in human skin.

Irritation

low

Source

natural

beautyskincareantioxidant
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Soothing Agent

Eupatorium Fortunei Extract

EUPATORIUM FORTUNEI EXTRACT

3.8

A gentle botanical extract with traditional use for soothing skin, though modern research is still limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Soothing Agent

Eupatorium Lindleyanum Extract

EUPATORIUM LINDLEYANUM EXTRACT

3.8

A gentle botanical extract with antioxidant potential, but research on its skincare benefits is still limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

Eupenicillium Crustaceum Ferment

Eupenicillium Crustaceum Ferment Lysate Extract Filtrate

4.0

A gentle, biotech-derived antioxidant that may help protect skin from environmental stress and support a more even tone.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Antioxidant

Euphorbia Jolkini Extract

EUPHORBIA JOLKINII EXTRACT

3.5

A gentle plant extract with antioxidant potential, but research is limited and it may cause sensitivity in some individuals.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Euphorbia Lathyris Seed Extract

EUPHORBIA LATHYRIS SEED EXTRACT

3.5

A plant extract with potential antioxidant and soothing benefits, but limited research and a known risk of skin irritation for sensitive individuals.

Irritation

moderate

Source

natural

beautyskincarebotanical extract
Read ingredient review

Soothing Agent

Euphorbia Supina Extract

EUPHORBIA SUPINA LEAF/STEM EXTRACT

3.5

A gentle plant extract with traditional use for soothing skin, but scientific backing is still limited.

Irritation

low

Source

natural

beautyskincaresoothing agent
Read ingredient review

Soothing Agent

Euphorbia Supina Stem Extract

EUPHORBIA SUPINA STEM EXTRACT

3.5

A gentle botanical extract with potential soothing and antioxidant benefits, but research is limited.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Antioxidant

European Larch Wood Extract

Larix Europaea Wood Extract

3.8

A gentle, plant-based extract that may help calm skin and fight free radicals, but research is still limited.

Irritation

low

Source

natural

beautyskincareantioxidant
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Colorant

Europium Chloride

EUROPIUM CHLORIDE

2.5

A rare earth salt used for color, but with limited safety data and potential for irritation in sensitive individuals.

Irritation

moderate

Source

synthetic

beautyskincarecolorant
Read ingredient review

Colorant

Europium Complex

EUROPIUM TRIS(TRIFLUOROTHIENYLBUTANEDIONE) BIS(TRIPHENYLPHOSPHINE OXIDE)

2.5

A rare synthetic colorant with limited safety data; best reserved for occasional-use products.

Irritation

low

Source

synthetic

beautyskincarecolorant
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Antioxidant

Eurya Emarginata Extract

Eurya Emarginata Leaf/Twig Extract

3.8

A gentle botanical extract with antioxidant potential, but research is still early and benefits are not yet proven in human skin.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Eurya Japonica Extract

Eurya Japonica Extract

3.8

A gentle plant extract with antioxidant potential, but research is still early and benefits are not yet proven in human studies.

Irritation

low

Source

natural

beautyskincareantioxidant
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Emollient

Euryale Ferox Seed Oil

EURYALE FEROX SEED OIL

4.0

A gentle, antioxidant-rich oil that hydrates and softens skin without clogging pores, suitable for most skin types.

Irritation

low

Source

natural

beautyskincareemollient
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Antioxidant

Eutreptiella Gymnastica Lysate

EUTREPTIELLA GYMNASTICA LYSATE

4.0

A gentle, antioxidant-rich microalgae ingredient that may help calm skin and defend against environmental stress.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Emollient

Evening Primrose & Palm Oil Esters

EVENING PRIMROSE OIL/PALM OIL AMINOPROPANEDIOL ESTERS

3.8

A gentle emollient that combines the fatty acid benefits of evening primrose oil with a stable, esterified form for smoother skin.

Irritation

low

Source

semi-synthetic

beautyskincareemollient
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Antioxidant

Evening Primrose Extract

OENOTHERA BIENNIS FLOWER/LEAF/STEM EXTRACT

4.0

A gentle, plant-based extract that helps calm skin and defend against environmental stress, though research is still emerging.

Irritation

low

Source

natural

beautyskincareantioxidant
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Antioxidant

Evening Primrose Leaf Cell Extract

Oenothera Biennis Leaf Cell Extract

3.8

A gentle, plant-derived antioxidant that may help protect skin from environmental stress, though research is still emerging.

Irritation

low

Source

biotech

beautyskincareantioxidant
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Soothing Agent

Evening Primrose Leaf Extract

OENOTHERA BIENNIS LEAF EXTRACT

3.8

A gentle botanical extract that may help calm skin and provide antioxidant protection, but research is limited compared to the seed oil.

Irritation

low

Source

natural

beautyskincarebotanical extract
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Emollient

Evening Primrose Oil

Oenothera Biennis Oil

4.0

Evening primrose oil is a gentle, nourishing oil that helps soothe dry or sensitive skin and supports a healthy moisture barrier.

Irritation

low

Source

natural

beautyskincareemollient
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Soothing Agent

Evening Primrose Root Extract

OENOTHERA BIENNIS ROOT EXTRACT

3.8

A gentle, plant-based extract that may help calm irritated skin and provide antioxidant protection, though research is still emerging.

Irritation

low

Source

natural

beautyskincarebotanical extract
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